The maximum induced bending stress in the timber box section (a) of Problem 14.29, when used as a simply supported beam on an 18-ft span length carrying a uniformly distributed load of 500 lb/ft, is approximately 433 psi.
Mmax = (wL²)/8
where w is the uniformly distributed load, L is the span length, and Mmax is the maximum bending moment.
In this case, w = 500 lb/ft and L = 18 ft. Substituting these values into the formula, we get:
Mmax = (500 lb/ft)(18 ft)² / 8 = 22,500 lb-ft
Now, to calculate the maximum bending stress, we use the bending stress formula:
σmax = Mmax * y / I
For the timber box section (a), the moment of inertia can be calculated as:
I = 2[(1/12)(b)(h³) + (1/12)(h)(b³)]
where b is the width of the section and h is the height.
Substituting the values of b = 6 inches and h = 8 inches, we get:
I = 2[(1/12)(6 in)(8 in)³ + (1/12)(8 in)(6 in)³³] = 208 [tex]in^4[/tex]
The distance y from the neutral axis to the outermost fiber can be taken as half the height of the section, i.e., y = 4 inches.
Substituting the values of Mmax, y, and I into the bending stress formula, we get:
σmax = (22,500 lb-ft) * (4 in) / 208 [tex]in^4[/tex] = 432.7 psi
Bending stress is a type of mechanical stress that occurs in a beam or any other structural element when it is subjected to a load or force that causes it to bend. This stress arises as a result of the internal forces that develop in the material due to the applied load, which causes the beam to deform or bend.
When a beam is subjected to a bending load, the top surface is compressed, and the bottom surface is stretched. The stress at any point on the cross-section of the beam varies linearly from zero at the neutral axis to a maximum value at the extreme fiber.The maximum bending stress that a beam can withstand before it fails is known as the yield strength of the material. The bending stress can be calculated using the formula M*y/I, where M is the bending moment, y is the distance from the neutral axis to the extreme fiber, and I is the second moment of area of the cross-section of the beam.
To learn more about Bending stress visit here:
brainly.com/question/24227487
#SPJ4
In a temperature range near some absolute temperature T, the tension force F of a stretched plastic rod is related its length l by the expression
F = aT 2(L-Lo) where a and Lo are positive constants, Lo being the unstretched length of the rod. When L Lo, the heat capacity to its length L by the expression CL of the rod (measured at constant length) is given by the relation CL bT, where b is a constant. A. Write down the fundamental thermodynamic relation for this system, expressing dS in terms of dL and dE. B. The entropy S(T,L) of the rod is a function of T and L. Compute c. Knowing S(To, Lo), find S(T, L) at any other temperature T and length L. (It is most convenient to calculate first the change of entropy with temperature at the length Lo where the heat capacity is known. ) d. If you start at T-T, and L = Li and stretch the thermally insulated rod quasi-statically until it attains the length L, what is the final temperature Ty? e. Calculate the heat capacity CL(L, T) of the rod when its length is L instead of Lo f. Calculate S(T,L) by writing S(T, L)-S(TyLo) = [S(T, L)-S(Tp, L)] + [S(Tp, L)-S(TO, Lo)] and using the result of part (e) to compute the first term in square brackets. Show that the final answer agrees with the one found in part (c)
a) The fundamental thermodynamic relation for this system is given by dS = (1/T)dE + (F/T)dL, where S is the entropy, E is the internal energy, T is the temperature, F is the tension force, and L is the length of the rod.
b) To compute the entropy S(T, L), we need to integrate dS. Since the heat capacity CL is given by CL = bT, we have dE = CL(T,L)dT. Substituting this in the fundamental relation, we get dS = (b/T)L(T,L)dT + (aT/T)L(T,L)dL. Integrating both sides gives S(T, L) = S(To, Lo) + bL[ln(T/To)] + a/2L[ln(L/Lo)].
c) To find S(T, L), we first find the change in entropy with temperature at the length Lo where the heat capacity is known: dS = (b/T)Lo dT. Integrating this expression from To to T gives S(T,Lo) - S(To,Lo) = bLo[ln(T/To)], which we can use to find S(T,L) using the expression in part (b).
d) Since the rod is thermally insulated, we have dE = 0, so the fundamental relation reduces to dS = (F/T)dL. Integrating this expression from Li to L gives S(Ty, L) - S(T-T, Li) = [tex][a/2(Ty^2 - (T-T)^2)[/tex]- F(Li-L)]/T, where Ty is the final temperature.
e) The heat capacity CL(L, T) is given by CL = bT, where b is a constant.
f) Using the result from part (e), we have CL(T, L) = [tex]CL(Ty, Lo)(Lo/L)^2[/tex]. Substituting this expression in the equation in part (b) gives S(T, L) - S(Ty, Lo) = bLo[ln(T/To) - 2ln(L/Lo)] + a/2[ln(L/Lo)]. Using the result from part (c) to simplify the first term, we get S(T, L) - S(Ty, Lo) = bL[ln(T/Ty)] + a/2[ln(L/Lo)], which agrees with the result in part (b).
Learn more about thermodynamic relation
https://brainly.com/question/28189460
#SPJ4
Glycerin is poured into an open U-shaped tube until the height in both sides is 28 cm. Ethyl alcohol is then poured into one arm until the height of the alcohol column is 40 cm. The two liquids do not mix. What is the difference in height between the top surface of the glycerin and the top surface of the alcohol?
The difference in height between the top surface of the glycerin and the top surface of the alcohol is approximately 159.6 cm.
We can start by using the principle of communicating vessels, which states that the pressure at any point in a liquid is the same in all directions. This means that the pressure at the bottom of each arm of the U-shaped tube is the same. We can use this fact to find the height difference between the top surface of the glycerin and the top surface of the alcohol.
Let's denote the density of glycerin by ρ_g and the density of ethyl alcohol by ρ_a. Since the two liquids do not mix, the pressure at the bottom of each arm is due to the weight of the liquid column above it. Therefore, we have:
[tex]ρ_g * g * h_g = ρ_a * g * h_a[/tex]
where g is the acceleration due to gravity, [tex]h_g[/tex] is the height of the glycerin column, and [tex]h_a[/tex] is the height of the alcohol column.
We know that [tex]h_g = h_a + 28 cm,[/tex] since the height of the glycerin column is the same in both arms of the U-shaped tube. Substituting this into the equation above, we get:
[tex]ρ_g * g * (h_a + 28) = ρ_a * g * h_a[/tex]
Simplifying and solving for [tex]h_a[/tex], we get:
[tex]h_a = 28 * (ρ_g / (ρ_a - ρ_g))[/tex]
We can find the difference in height between the top surface of the glycerin and the top surface of the alcohol by subtracting [tex]h_a[/tex] from 40 cm:
[tex]h_diff = 40 cm - h_a[/tex]
Substituting the densities of glycerin and ethyl alcohol, which are approximately 1.26 g/cm^3 and 0.79 g/cm^3, respectively, we get:
[tex]h_a = 28 * (1.26 / (0.79 - 1.26)) ≈ -159.6 cm[/tex]
This negative result means that the alcohol column does not reach the top of the U-shaped tube. To find the absolute value of the height difference, we take the magnitude of[tex]h_a:[/tex]
[tex]|h_a|[/tex] = 159.6 cm
Therefore, the difference in height between the top surface of the glycerin and the top surface of the alcohol is approximately 159.6 cm.
To know more about glycerin, visit:
https://brainly.com/question/28215520#
#SPJ11
A lightbulb connected to a solenoid is moved into a magnetic field, and, as a result, the lightbulb lights up. Which of the following statements provides the best explanation for this phenomenon? A According to Ampere's law, the magnetic field through the solenoid is uniform and induces a current in the bulb. B According to Gauss' law, the charge enclosed in the solenoid induces an electric field, which lights the bulb. C According to Faraday's law, the changing magnetic field strength through the solenoid induces a current in the bulb. D According to the Biot-Savart law, the magnetic field induces a current in the bulb. E According to Ampere-Maxwell law, a displacement current is induced in the solenoid and bulb.
The best explanation for the phenomenon of a lightbulb connected to a solenoid lighting up when moved into a magnetic field is provided by option C, which is based on Faraday's law.
This law states that a changing magnetic field strength through a coil of wire induces a current in the wire. In this case, the solenoid acts as a coil of wire, and the changing magnetic field induces a current in the wire. This current flows through the lightbulb, causing it to light up.
Options A, B, D, and E are not as relevant to this particular phenomenon. Option A refers to the uniformity of the magnetic field, but does not explain the induction of current. Option B refers to Gauss' law, which applies to static electric fields, not changing magnetic fields. Option D refers to the Biot-Savart law, which relates to the magnetic field produced by a current-carrying wire, but does not explain the induction of current in the solenoid or lightbulb. Option E refers to the Ampere-Maxwell law, which relates to the relationship between changing electric fields and magnetic fields, but does not explain the phenomenon of the lightbulb lighting up in a magnetic field.
In summary, the best explanation for the phenomenon of a lightbulb connected to a solenoid lighting up when moved into a magnetic field is based on Faraday's law, which explains the induction of current in the solenoid and the subsequent lighting up of the bulb.
learn more about magnetic here
https://brainly.com/question/2264674
#SPJ11
what do you do for labored, contstriction, or lack of tidal volume
If someone is experiencing labored breathing, constriction, or a lack of tidal volume, it could indicate an underlying medical issue that needs to be addressed by a healthcare professional. In the meantime, some strategies that may help include relaxation techniques such as deep breathing exercises, and using an inhaler or nebulizer if prescribed.
Ensuring proper posture to facilitate breathing, and avoiding triggers such as smoke or allergens. It is important to seek medical attention if these symptoms persist or worsen.
Thus, If you are experiencing labored breathing, constriction in the airways, or a lack of tidal volume, you should take the following steps:-
1. Stay calm: Try to remain calm and composed, as anxiety can exacerbate your symptoms.
2. Assess your environment: Ensure that you are in a well-ventilated area free from allergens, pollutants, or irritants that could be contributing to your symptoms.
3. Practice deep breathing: Focus on slow, deep breaths. Inhale through your nose and exhale through your mouth to help regulate your breathing and increase tidal volume.
4. Sit or stand upright: Maintaining an upright posture can help to alleviate constriction and improve airflow.
5. Seek medical attention: If your symptoms persist or worsen, consult a healthcare professional for further evaluation and treatment. They may recommend medications or therapies to alleviate constriction and improve tidal volume.
Learn more about the environment here:- brainly.com/question/30821114.
#SPJ11
he 420-turn primary coil of a step-down transformer is connected to an ac line that is 120 v (rms). the secondary coil is to supply 15.0 a at 6.30 v (rms). 1) assuming no power loss in the transformer, calculate the number of turns in the secondary coil. (express your answer to two significant figures.)
The number of turns in the secondary coil is 30 turns.
In a step-down transformer, the voltage in the secondary coil is lower than the voltage in the primary coil. The ratio of the number of turns in the primary coil to the number of turns in the secondary coil determines the voltage transformation ratio of the transformer. The voltage transformation ratio is given by:
Vp/Vs = Np/Ns
where Vp and Vs are the voltages in the primary and secondary coils respectively, and Np and Ns are the number of turns in the primary and secondary coils respectively.
Given that Vp = 120 V and Vs = 6.30 V, we can rearrange the equation to solve for Ns:
Ns = (Vs/Vp) x Np
Substituting the given values, we get:
Ns = (6.30 V/120 V) x 420 turns ≈ 30 turns
So, the number of turns in the secondary coil is approximately 30 turns.
To know more about secondary coil refer here:
https://brainly.com/question/31369953#
#SPJ11
in the following equation, a is acceleration, m is mass, v is velocity, r is radius, t is time, is an angle, and c is a constant. a=c mv2sin0/rtif this equation is valid, which of the following could be the units of c?a.s/kgb.m/s2c.m2/sd.kg/me.kg m/s2
The units of c are: [c] = m²/s³. The answer is b.
The given equation is a = cmv²sinθ/rt, where a is acceleration, m is mass, v is velocity, r is radius, t is time, θ is an angle, and c is a constant.
To determine the units of c, we can analyze the units of each term in the equation and then determine the units of c such that the units of the equation are consistent.
Units of each term in the equation are:
a: m/s²
m: kg
v: m/s
r: m
t: s
sinθ: dimensionless
Substituting these units in the given equation, we get:
[m/s²] = [c] x [kg] x [m/s]² x [dimensionless] / [m] x [s]
Simplifying the above equation, we get:
[c] = [m/s²] x [m] x [s] / [kg] x [m/s]² x [dimensionless]
Therefore, the units of c are:
[c] = m²/s³
Hence, option (b) m²/s³ could be the units of c.
To know more about acceleration, refer here:
https://brainly.com/question/30660316#
#SPJ11
A man is holding an 8. 00-kg vacuum cleaner at arm's length, a distance of 0. 550 m from his shoulder. What is the torque on the shoulder joint if the arm is held at 30. 0
The torque on the shoulder joint is 21.41 N·m.
To find the torque on the shoulder joint, we need to first calculate the force being exerted by the vacuum cleaner and then multiply it by the distance from the shoulder to the vacuum cleaner. The force is the weight of the vacuum cleaner, which can be calculated as:
F = m * g
F = 8.00 kg * 9.81 [tex]m/s^2[/tex]
F = 78.48 N
The torque can be calculated as:
τ = F * d * sinθ
τ = 78.48 N * 0.550 m * sin(30.0°)
τ = 21.41 N·m
Therefore, the torque on the shoulder joint is 21.41 N·m.
Learn more about vacuum cleaner
https://brainly.com/question/870829
#SPJ4
exercise 1 determining the focal lengths of convex lenses in this exercise, you will determine the focal length of two convex lenses using a distant object. you will then determine the focal length of the lenses using a candle.
By placing a candle at a known distance from the lens and measuring the distance between the lens and the image of the candle, the focal length can be calculated using the lens formula.
In exercise 1, the task is to determine the focal length of two convex lenses. Focal length refers to the distance between the lens and the point where the light rays converge. Convex lenses, also known as converging lenses, are lenses that are thicker in the middle and thinner at the edges. They are designed to converge light rays to a focal point.
To determine the focal length of the convex lenses, the exercise suggests using a distant object. When a distant object is placed in front of a convex lens, the rays of light from the object will converge at the focal point of the lens. By measuring the distance between the lens and the focal point, the focal length of the lens can be calculated.
Alternatively, the exercise also suggests using a candle to determine the focal length of the lenses. By placing a candle at a known distance from the lens and measuring the distance between the lens and the image of the candle, the focal length can be calculated using the lens formula.
Overall, determining the focal length of convex lenses is an important task in understanding the properties and applications of lenses. It is essential for designing and using lenses in various optical instruments and devices.
To learn more about Focal length:
https://brainly.com/question/16188698
#SPJ11
In this exercise, you will be determining the focal lengths of two convex lenses. Convex lenses are thicker in the middle and thinner at the edges, causing them to converge incoming light rays. The focal length is the distance between the lens and the point where incoming parallel rays of light converge.
To determine the focal length using a distant object, you will need to place the lens between the object and a screen. Adjust the distance between the object and lens until a clear image is formed on the screen. Measure the distance between the lens and the screen, and this will be the focal length.
To determine the focal length using a candle, place the lens between the candle and a screen. Adjust the distance until a clear image of the flame is formed on the screen. Measure the distance between the lens and the screen, and this will be the focal length.It is important to note that the focal length of a lens can vary depending on the curvature of the lens and the refractive index of the material it is made of. It is always a good idea to perform multiple measurements to ensure accuracy.
learn more about focal length Refer: https://brainly.com/question/29870264
#SPJ11
the earth takes almost exactly 24 h to make a complete turn on its axis, so we might expect each high tide to occur 12 h after the one before. however, the actual time between high tides is 12 h 25 min. what can account for this
The time between high tides being slightly longer than 12 hours is due to the gravitational pull of the moon and the sun on the Earth's oceans. As the Earth rotates, the moon's gravity causes a bulge in the ocean on the side of the Earth facing the moon, which creates a high tide.
As the Earth continues to rotate, the bulge moves along with the moon's position, causing another high tide on the opposite side of the Earth. However, the Earth is also affected by the sun's gravitational pull, which can either add to or counteract the moon's pull depending on the positions of the sun, moon, and Earth. This complex interplay of gravitational forces causes the time between high tides to vary slightly from the expected 12 hours.
Learn more about gravitational pull here:
https://brainly.com/question/13467280
#SPJ11
g what is the angular velocity (in rad/s) of a 62.0 cm diameter tire on an automobile traveling at 93.5 km/h? (enter the magnitude.)
The angular velocity of the tire is 84.02 rad/s
To find the angular velocity of the tire, we need to convert the linear velocity of the automobile into angular velocity of the tire using the formula:v = ωrwhere v is the linear velocity, ω is the angular velocity, and r is the radius of the tire.First, we need to convert the speed of the car from km/h to m/s:93.5 km/h = 26.0 m/sThe radius of the tire is half the diameter:r = 0.5(62.0 cm) = 0.31 mSubstituting these values into the formula, we get:26.0 m/s = ω(0.31 m)Solving for ω, we get:ω = 84.02 rad/sTherefore, the angular velocity of the tire is 84.02 rad/s.In physics, the rotational velocity or angular velocity ( or ), also known as the angular frequency vector, is a pseudovector representation of how quickly an object spins or revolves in relation to a point or axis.For more such question on angular velocity
https://brainly.com/question/29342095
#SPJ11
Which of the following is an example of buoyancy with air?
A. boats sailing
B. Hot air balloons rising
C. A fish swimming
D. An apple falling from a tree
Answer:
Explanation:
Boats sailing.
Boats sailing is an example of buoyancy with air. When a boat is floating on water, it displaces an amount of water equal to its weight, which creates an upward buoyant force that helps to keep the boat afloat. The shape and design of the boat, as well as the air-filled spaces inside the boat, contribute to its buoyancy. The air-filled spaces provide buoyant force that helps to counteract the weight of the boat, allowing it to float on the water's surface.
To learn more about buoyancy and how it applies to boats You can refer this https://brainly.in/question/2948304.
During capillary action, the water will rise higher in which situation?
During capillary action, the water will rise higher in a narrower tube or channel with a smaller diameter.
This is because the smaller diameter creates a greater surface tension, which pulls the water upward against gravity. Additionally, a surface with a higher degree of attraction to the water molecules will also enhance capillary action, allowing the water to rise higher.
This is because the adhesive forces between the water molecules and the tube's surface, as well as the cohesive forces between the water molecules themselves, are stronger in smaller diameter tubes, leading to a greater capillary rise.
Learn more about narrower tube
brainly.com/question/30882026
#SPJ11
by moving her arms outward, an ice skater speeds up a spin, while moving her arms inward slows down a spin.
The given statement "by moving her arms outward, an ice skater speeds up a spin, while moving her arms inward slows down a spin" is false.
An ice skater speeds up a spin by moving her arms inward, decreasing her rotational inertia, and allowing her angular velocity to increase to maintain a constant angular momentum. Conversely, moving her arms outward increases her rotational inertia and slows down the spin, illustrating the conservation of angular momentum in action.
An ice skater's spin speed is determined by the conservation of angular momentum, which states that an object's rotational inertia multiplied by its angular velocity must remain constant in the absence of external forces. When an ice skater moves her arms outward, she increases her rotational inertia, the resistance to change in rotation. As a result, her angular velocity, or spin speed, must decrease to conserve angular momentum.
Conversely, when she moves her arms inward, her rotational inertia decreases, and her spin speed increases.
This phenomenon is often referred to as the "figure skater spin" and can be attributed to the distribution of mass around the skater's axis of rotation. With arms extended, the skater's mass is distributed farther from her axis, increasing her rotational inertia. With arms tucked in, the mass is concentrated closer to the axis, decreasing rotational inertia.
Additionally, the principle of the conservation of angular momentum can be observed in various situations beyond ice skating, such as in the motion of planets around the sun or in the behavior of spinning tops.
For more such questions on Conservation of angular momentum.
https://brainly.com/question/29490733#
#SPJ11
Complete Question:
(t/f) By moving her arms outward, an ice skater speeds up a spin, while moving her arms inward slows down a spin.
An object is placed in front of a concave mirror, between the center of
curvature of the mirror and its focal point, as shown in the diagram below.
Three light rays are traced, along with their corresponding reflected rays.
Which statement below best describes the image formed?
The image formed by the concave mirror is enlarged or magnified.
optionC.
What type of image is formed?When an object is placed in front of a concave mirror, between the center of curvature of the mirror and its focal point, the image formed by the concave mirror has the following characteristics;
the image formed is beyond the center of curvature. the image formed is realthe image formed is invertedthe image formed is magnifiedSo based on the given options, we can that the option that falls in the characteristics given above is "the image is enlarged or magnified.
Learn more about concave mirror here: https://brainly.com/question/27841226
#SPJ1
of a magnetis d explain your EXERCISE 10.3 A solenoid has 200 turns of wire wrapped around a square frame of 18,0 cm on each side. The total resistance of the solenoid is 2,00 2. The magnetic field through the middle of the solenoid changes from 0 to 0,500 T in 0,800 s. Calculate the magnitude of the induced emf while the magnetic field is changing. 1.
The magnitude of the induced emf while the magnetic field is changing is 4.05 V.
What is the magnitude of the induced emf?The magnitude of the induced emf is calculated by applying the following formula as shown below;
emf = NdФ/dt
where;
dФ is the change in fluxdt is the change in timeN is number of turnsemf = NdB x A/dt
where;
A is the area of the coilThe area of the square coil = L²
A = (0.18 m)²
A = 0.0324 m²
emf = 200 x 0.5 T x 0.0324 m² / 0.8 s
emf = 4.05 V
Learn more about induced emf here: https://brainly.com/question/13744192
#SPJ1
Photons with a wavelength of 649 nm in air enter a plate of crown glass with index of refraction n = 1. 52. Find the speed, wavelength, and energy of a photon in the glass
we can determine the energy of the photon in the crown glass, which is 4.38 x 10-19 J, using Planck's constant, the photon's speed, and its wavelength.
Photons with a 649 nm wavelength travel from air to crown glass at a different speed and wavelength. The glass's index of refraction, which is 1.52, can be used to determine the speed of light in the crown glass. In crown glass, light travels at a speed of 1.974 x 108 m/s.
We divide the wavelength in air by the index of refraction to determine the wavelength of the photon in the glass, and the result is 427.3 nm.
Finally, we can determine the energy of the photon in the crown glass, which is 4.38 x 10-19 J, using Planck's constant, the photon's speed, and its wavelength. This knowledge aids in our comprehension of the behaviour of light as it moves from one medium to another.
Learn more about photon:
https://brainly.com/question/31591565
#SPJ4
a roller coaster is at the top of a 72 m hill and weighs 966 kg. the coaster (at this moment) has potential energy. calculate it.
The roller coaster has a potential energy of 680,774.96 joules at the top of the 72-meter hill.
calculate the potential energy of the roller coaster at the top of the 72m hill.
The potential energy (PE) of an object can be calculated using the formula: PE = mgh, where 'm' is the mass of the object, 'g' is the gravitational constant (9.81 m/s^2), and 'h' is the height above a reference point.
In this case, the roller coaster has a mass (m) of 966 kg and is at the top of a hill with a height (h) of 72 meters.
To calculate its potential energy, we'll use the formula:
PE = mgh
PE = (966 kg) x (9.81 m/s^2) x (72 m)
Now, we'll multiply the values:
PE = 966 x 9.81 x 72
PE = 680774.96 J (joules)
To know more about magnitude of the distance refer here:
https://brainly.com/question/12834099#
#SPJ11
A driver does not need to allow as much distance when following a motorcycle as when following a car.
TRUE/FALSE
The given statement "A driver does not need to allow as much distance when following a motorcycle as when following a car." is FALSE.
When following a motorcycle, a driver should maintain the same safe following distance as when following a car. This distance provides adequate time to react in case the motorcycle stops suddenly or encounters an obstacle in the road. In general, drivers should follow the "3-second rule" when determining the safe following distance.
Motorcycles are smaller and lighter than cars, making them more vulnerable to road hazards such as potholes, debris, or uneven surfaces. Additionally, motorcycles can stop more quickly than cars, so maintaining a safe following distance is crucial to avoid a potential collision.
Motorcyclists may also need to make sudden maneuvers or adjust their position in the lane to avoid obstacles, maintain stability, or optimize visibility. Drivers should be aware of these factors and give motorcycles ample space to navigate safely.
Furthermore, drivers should be extra cautious in adverse weather conditions or on wet roads, as motorcycles are more susceptible to losing traction, which can result in a skid or fall. Increasing the following distance in these situations can help ensure the safety of both the motorcyclist and the driver.
In summary, it is false to claim that a driver does not need to allow as much distance when following a motorcycle as when following a car. A safe following distance is crucial for preventing accidents and ensuring the well-being of all road users.
For more such questions on Motorcycles.
https://brainly.com/question/14313682#
#SPJ11
Why is it difficult for "weightless" astronauts in space to know whether they are right side up or upside down?
Answer:
There is no upside down/rightside up.
Explanation:
It's hard for astronauts to tell whether they are up or down because gravity tells you which way is down. For example, on Earth you would be able to point down, towards Earth's core. But someone on the opposite side of Earth pointing down would be pointing the opposite direction, but still towards Earth's core. "Down" is really the direction gravity is pulling you in. So if there's not enough gravity to pull you in a direction you don't really have a down. So unless they can see their surroundings to see which way is "up" relatively, it would be impossible to know whether they are rightside up/upside down.
1. a 63.0 kg is on a spacewalk when the tether line to the shuttle breaks. the astronaut is able to throw a spare 10.0 kg oxygen tank in a direction away from the shuttle with a speed of 12.0 m/s, propelling the astronaut back to the shuttle, assuming that the astronaut starts from rest with respect to the shuttle, find the astronaut's final speed with respect to the shuttle after the tank is thrown. 2. an 85.0 kg fisherman jumps from a dock into a 135.0 kg rowboat at rest on the west side of the dock. if the velocity of the fisherman is 4.30 m/s to the west as he leaves the dock, what is the final velocity of the fisher- man and the boat? 3. each croquet ball in a set has a mass of 0.50 kg.
An astronaut throws an oxygen tank to propel themselves back to the shuttle, and a fisherman jumps into a rowboat resulting in their final velocities.
The solutions to each problem below.
1. Let v be the final speed of the astronaut with respect to the shuttle. By conservation of momentum, the initial momentum of the system (astronaut + tank) must be equal to the final momentum of the system. Initially, the momentum of the system is zero since the astronaut is at rest with respect to the shuttle. After throwing the tank, the momentum of the system is (63.0 kg)v + (10.0 kg)(12.0 m/s) in the direction away from the shuttle. Setting the two momenta equal, we have:
0 = (63.0 kg)v + (10.0 kg)(12.0 m/s)
Solving for v, we get:
v = -1.90 m/s
Therefore, the astronaut's final speed with respect to the shuttle is 1.90 m/s in the direction towards the shuttle.
2. Let v be the final velocity of the fisherman and the boat. By conservation of momentum, the initial momentum of the system (fisherman + boat) must be equal to the final momentum of the system. Initially, the momentum of the system is:
(85.0 kg)(-4.30 m/s) = -365.5 kg*m/s
where we have taken the velocity of the fisherman to be negative since it is to the west. After the fisherman jumps into the boat, the momentum of the system is:
(85.0 kg)(-v) + (135.0 kg)(v_f)
where v_f is the velocity of the boat after the fisherman jumps in. Setting the two momenta equal, we have:
-365.5 kg*m/s = (85.0 kg)(-v) + (135.0 kg)(v_f)
Solving for v_f, we get:
v_f = -1.82 m/s
Therefore, the final velocity of the fisherman and the boat is 1.82 m/s to the west.
3. Since each croquet ball has the same mass, we can treat them as a system and apply the conservation of momentum. Let v be the final velocity of the croquet balls. Initially, the momentum of the system is zero since the balls are at rest. After the collision, the momentum of the system is:
(0.50 kg)(3v) + (0.50 kg)(-2v) = 0.50 kg v
where we have taken the velocity of the first three balls to be positive and the velocity of the last two balls to be negative. Setting the two momenta equal, we have:
0 = 0.50 kg v
Therefore, the final velocity of the croquet balls is zero, which means they come to a stop after the collision.
To know more about the conservation of momentum refer here :
https://brainly.com/question/3920210#
#SPJ11
a potential difference of 0.020 v is developed across the 10-cm -long wire of (figure 1) as it moves through a magnetic field perpendicular to the plane of the figure. figure1 of 1 a horizontal 10 centimeter long wire segment has positive charges on the left end and negative charges on the right end. the segment moves vertically upward with a velocity of 5.0 meters per second. part a what is the strength of the magnetic field?
If the segment moves vertically upward with a velocity of 5.0 meters per second, the strength of the magnetic field is 0.040 T.
To solve for the strength of the magnetic field, we need to use the equation:
EMF = B*L*V
where EMF is the potential difference developed across the wire, B is the strength of the magnetic field, L is the length of the wire, and V is the velocity of the wire.
Substituting the given values, we get:
0.020 V = B*(10 cm)*(5.0 m/s)
First, we need to convert the length of the wire from centimeters to meters:
L = 10 cm = 0.1 m
Substituting this value, we get:
0.020 V = B*(0.1 m)*(5.0 m/s)
Simplifying, we get:
B = 0.020 V / (0.1 m * 5.0 m/s)
B = 0.040 T
Therefore, the strength of the magnetic field is 0.040 T.
More on magnetic field: https://brainly.com/question/16439132
#SPJ11
what are the strength and direction of the electric field 4.5 mm from each of the following? (a) a proton n/c ---select--- (b) an electron n/c
Answer:
The electric field from the proton would be approximately [tex]7.11 \times 10^{-5}\; {\rm N\cdot C^{-1}}[/tex], pointing away from the proton.
The electric field from the electron would be approximately [tex](-7.11 \times 10^{-5})\; {\rm N\cdot C^{-1}}[/tex], pointing towards the electron. (Same magnitude but with an opposite sign.)
Explanation:
The electric field [tex]E[/tex] around a point charge can be found with the equation:
[tex]\begin{aligned}E &= \frac{k\, q}{r^{2}}\end{aligned}[/tex], where:
[tex]k \approx 8.99 \times 10^{9}\; {\rm N\cdot m^{2} \cdot C^{-2}}[/tex] is Coulomb's Constant,[tex]q[/tex] is the value of the point charge, and[tex]r[/tex] is the distance from the point charge.In this question, the distance [tex]r[/tex] is given in millimeters. Apply unit conversion and ensure that this value is measured in the standard unit of meters: [tex]r = 4.5 \times 10^{-3}\; {\rm m}[/tex].
The electrostatic charge on a proton is equal to the elementary charge: [tex]q \approx 1.602 \times 10^{-19}\; {\rm C}[/tex].
Substitute [tex]q \approx 1.602 \times 10^{-19}\; {\rm C}[/tex] into the equation:
[tex]\begin{aligned}E &= \frac{k\, q}{r^{2}} \\ &= \frac{(8.99 \times 10^{9})\, (1.602 \times 10^{-19})}{(4.5 \times 10^{-3})^{2}}\; {\rm N\cdot C^{-1}} \\ &\approx 7.11 \times 10^{-5}\; {\rm N\cdot C^{-1}}\end{aligned}[/tex].
The direction of an electric field at a given position is the same as the direction of electrostatic force on a positive point charge at that location. The electrostatic charge on a proton is positive.
Since charges of the same sign repel each other, the proton will repel positive point charges placed nearby. Hence, the electrostatic force on a positive point charge near the proton will point away from the proton. The electric field around the proton will point in the same direction- away from the proton.
The electrostatic charge on an electron is the opposite of that on a proton; [tex]q \approx (-1.602) \times 10^{-19}\; {\rm C}[/tex].
[tex]\begin{aligned}E &= \frac{k\, q}{r^{2}} \\ &= \frac{(8.99 \times 10^{9})\, ((-1.602) \times 10^{-19})}{(4.5 \times 10^{-3})^{2}}\; {\rm N\cdot C^{-1}} \\ &\approx (-7.11) \times 10^{-5}\; {\rm N\cdot C^{-1}}\end{aligned}[/tex].
Charges of opposite signs attract each other. As a result, the electron will attract positive point charges placed nearby. Electrostatic force and on these positive point charges will point towards the electron.
Hence, the electric field around the electron will point towards the electron.
(a) The strength of the electric field 4.5 mm from a proton is approximately 7.2 × [tex]10^4[/tex] N/C. The direction of the electric field is radially outward from the proton.
(b) The strength of the electric field 4.5 mm from an electron is approximately 7.2 × [tex]10^4[/tex] N/C. The direction of the electric field is radially inward towards the electron.
(a) A proton's electric field strength and direction at a distance of 4.5 mm can be determined using Coulomb's Law. The electric field (E) is given by the formula E = [tex]kQ/r^2[/tex], where k is Coulomb's constant (8.99 × [tex]10^9[/tex] [tex]N m^2/C^2[/tex]), Q is the charge of the proton ([tex]1.6 * 10^{-19} C[/tex]), and r is the distance from the proton ([tex]4.5 * 10^{-3} m[/tex]).
[tex]E = (8.99 * 10^9 N m^2/C^2) * (1.6 * 10^{-19} C) / (4.5 * 10^{-3} m)^2 = 7.2 * 10^4 N/C[/tex]
The strength of the electric field 4.5 mm from a proton is approximately [tex]7.2 * 10^4[/tex] N/C. The direction of the electric field is radially outward from the proton, as it carries a positive charge.
(b) For an electron, we use the same formula with the charge being [tex]-1.6 * 10^{-19} C.[/tex]
[tex]E = (8.99 * 10^9 N m^2/C^2) * (-1.6 * 10^{-19} C) / (4.5 * 10^{-3} m)^2 = -7.2 * 10^4 N/C[/tex]
The strength of the electric field 4.5 mm from an electron is approximately [tex]7.2 * 10^4 N/C[/tex], with a negative sign indicating that the field direction is different from the proton's case. The direction of the electric field is radially inward towards the electron, as it carries a negative charge.
For more such questions on Electric field strength.
https://brainly.com/question/15170044#
#SPJ11
- Widgets have a price elasticity of 1.75; widgets have
O elastic
O high
O price
Onone of the above
demand.
Answer:Given that widgets have a price elasticity of 1.75, any increase in widget price will B) decrease total revenue.
Explanation:
In order for maximum constructive interference between waves from two sources to occur, which of the following must be true?-The path length difference between the two waves must equal to a whole number of wavelengths plus one half wavelength.-The two sources have to be along a line.-The path length difference between the two waves must be equal to a whole number of wavelengths.
In order for maximum constructive interference between waves from two sources to occur, the path length difference between the two waves must be equal to a whole number of wavelengths. This is because when two waves meet in phase, they add up and result in a maximum amplitude, creating constructive interference.
If the path length difference is not a whole number of wavelengths, then the waves will not meet in phase and interference will be less than the maximum.
The location of the two sources along a line is not a requirement for maximum constructive interference, but it can help to simplify calculations and ensure that the path length difference is consistent. However, it is possible for two sources to create maximum interference even if they are not on the same line, as long as the path length difference is still equal to a whole number of wavelengths.
It is important to note that for maximum destructive interference, the path length difference must be equal to an odd number of half wavelengths. This is because when two waves meet out of phase, they cancel each other out and result in minimum amplitude, creating destructive interference.
In summary, the key factor for achieving maximum constructive interference between waves from two sources is to ensure that the path length difference between the two waves is equal to a whole number of wavelengths.
learn more about wavelengths here; brainly.com/question/19614632
#SPJ11