The wide wood pores that link to the tree's roots allow sap to be drawn up into the maple tree when it starts to freeze. The tree is really replenishing itself with fluids at this time from its roots.
As long as the temperature is below freezing and the sap is increasing, the process continues.
How does the xylem sap of tall trees go from the roots to the top?Water is drawn up from the roots to the top of the plant according to the cohesion-tension hypothesis of sap ascent. Water and minerals travel upward from the roots through the xylem due to a negative water potential gradient created by the evaporation of mesophyll cells in the leaves.
The water potential gets increasingly negative as you climb the tree, and these variations provide a pull or tension that causes the water to ascend the tree. The loss of water from the leaves through a process called transpiration is a crucial element in the draw of water up the tree.
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a 1.92 kg object on a frictionless horizontal track is attached to the end of a horizontal spring whose force constant is 4.77 n/m. the object is displaced 5.31 m to the right from its equilibrium position and then released, which initiates simple harmonic motion. what is the magnitude of the force acting on the object 3.72 s after it is released? answer in units of n.
The magnitude of the force acting on the object of mass 1.92 kg, 3.72 s after it is released is 23.414 N in negative direction.
ω = √ ( k / m )
ω = Angular frequency
k = Force constant
m = Mass
k = 4.77 N / m
m = 1.92 kg
ω = √ 4.77 / 1.92
ω = √ 2.48
ω = 1.58 rad / s
F ( t ) = - m d ω² cos ω t
F ( t ) = Force wrt time
d = Displacement
t = Time
t = 3.72 s
d = 5.31 m
F ( 3.72 ) = - 1.92 * 5.31 * 1.58² cos ( 1.58 * 3.72 )
F ( 3.72 ) = - 25.45 cos 5.88
F ( 3.72 ) = - 23.414 N
Therefore, the magnitude of the force acting on the object is 23.414 N in negative direction.
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magnus has reached the finals of a strength competition. in the first round, he has to pull a city bus as far as he can. one end of a rope is attached to the bus and the other is tied around magnus's waist. if a force gauge placed halfway down the rope reads out a constant 1550 newtons while magnus pulls the bus a distance of 2.15 meters, how much work does the tension force do on magnus? the rope is perfectly horizontal during the pull.
The Work done by tension force on Magnus is
- 3225 Joule .
In the given question we have, one end of rope is tied around magnus waist and other attched to bus and he pulls the bus. The direction of tension force is just work done.
constant force = 1550 Newton
displacement = 2.15 meters
The direction of tension force is opposite to work done due to the tension force is reaction force to force of work done for pulling the bus.
work done by tension = W = - W₀
where W₀is horizontal work done by magnus during pulling.
so, W₀ = Fdcosθ
where , F---> force , d--> displacment and θ ---> angle between force and displacement
As we see whole work done in horizontal direction. So, angle between force and displacement is zero.
put all the vales in above formula we get ,
W₀= 1550× 2.15 cos0 = 1550×2.15 = 3225 Joule
W = - W₀ = - 3,225J
Hence, work done by tension force on Magnus is
- 3,225 Joule.
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What is the potential difference measured if the following voltmeter (refer to picture) is used and connected to the circuit via the 3V terminal?
The potential difference measured if the given voltmeter is used and connected to the circuit via the 3V terminal is 1.4 V.
The reading of voltmeter is taken for the row with 0, 1, 2 and 3 values. Each line indicates 0.1 volts. The distance between each smaller lines indicates 0.2 volts and the distance between each longer lines indicates 0.2 volts.
A voltmeter is a device used to measure the potential difference between two points in a circuit. Potential difference is also called as voltage. Its unit is volts.
V = IR
V = Voltage
I = Current
R = Resistance
Therefore, the potential difference measured is 1.4 V
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bird bones have air pockets in them to reduce their weight. this also gives them an average density significantly less than that of the bones of other animals. suppose an ornithologist weighs a bird bone in air and in water and finds its mass is 45.0 g and its apparent mass when submerged is 3.60 g (the bone is watertight). what mass of water is displaced?mass of water displaced:kg what is the volume of the bone?volume of the bone:m3 what is its average density?average density of the bone:kg/m3 question credit: openstax college physics
a) Mass of displaced water is 41.4 g or 0.0414 kg
b) Volume of the bone is 41.4 mL or 41.4 × 10⁻⁶m³
c) Average density of the bone is 1.09 g/ mL or 0.00109 × 10⁻⁶ Kg /m³
In the given question we have, the weight of some bird bones is measured in air outside of some water and the weight is 45.0 grams and the apparent weight in water is 3.60 grams. Now, we shall find out the weight of the displaced water? So the buoyant force is this difference between the weight of the bones out of the water and in the water, so the weight out of the water times g minus the weight in the water times g and then the g can be factored in and the buoyant force is also equal to the weight of the displaced fluid from Archimedes' principle
i.e., 45 × g - 3.60× g = weight/ mass of displaced water
weight of displaced water = 41.4 × g
g× mass of displaced water = 41.4 ×g
=> mass of displaced water = 41.2 grams
a) Mass of displaced water = 0.0414 Kg
b) the volume of the bones is going to be equal to the volume of water displaced.
We know that the density of water is the mass of water displaced divided by the volume of water. So the volume of water displaced is the weight of the water displaced divided by the density of the water.
Volume of water displaced = 41.4 grams / density of displaced water
density of water displaced = 1 grams / milliliters
So, the density of water is 41.4 milliliters or 41.4 ×10⁻⁶ m³
c) The average density of the bone is the weight of the bone divided by its volume,
Average density of bone = 45 grams / 41.4 mililitres
so it's value is 1.09 grams per milliliter or 0.00109 × 10⁻⁵ m³
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Substances in a(n)________
separate properties.
keep their separate properties, but in a(n)___________
the parts are bonded and do not keep their
Substances in a mixture keep their separate properties, but in a compound the parts are bonded and do not keep their separate properties.
Mixtures contains elements and compounds without any fixed ratio and not by any means of chemical bonds. The elements and compounds are physically mixed and so they will be visibly distinct.
Compounds contains elements in a fixed ratio and is connected by chemical bonds. They only contain one type of molecule. Since they are chemically combined the particles appear as one and is not visibly distinct.
Therefore, substances in a mixture keep their separate properties, but in a compound the parts are bonded and do not keep their separate properties.
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You are skiing and you push off from the top of the hill, giving yourself an initial velocity of 1 m/s. You accelerate down the hill at a rate of 2 m/s/s. What will your speed be after 10 seconds? How far will you have traveled after 10 seconds?
Using Equations of motion, speed after 10 seconds will be 21 m/s and the distance travelled after 10 seconds will be 110 m.
What are Equations of motion?
Equations of motion are thought of as the relationships that assist us in relating the physical quantities, such as distance traveled, time spent traveling there, acceleration, and initial and final velocities.
First equation of motion
The velocity-time relation is the name given to the fundamental equation of motion, v = u + at.Second equation of motion
The position-time relation can be defined as s = ut + 1 / 2at2 in the second equation of motion.Third equation of motion
v2 = u2+ 2as, the position-velocity relation, is the third equation of motion.Given, initial velocity, u = 1 m/s
acceleration, a = 2 m/s/s
time = 10 s
Using First equation of motion, we find the speed after 10 seconds.
v = u + at
v = 1 + 2 x10
v = 1 + 20
v = 21 m/s
Using Second equation of motion, we find the distance travelled after 10 seconds,
s = ut + 1 / 2at2
s = 1 x 10 + ( 2 x 10 x 10)/2
s = 10 + 100
s = 110 m.
Hence, after 10 seconds speed will be 21 m/s and distance will be 110 m.
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Projectile motion is a combination of _______________ motion in the horizontal direction, and ________________ motion in the vertical direction.
A. accelerated, accelerated
B. constant, constant
C. accelerated, constant
D. constant, accelerated
Projectile motion is a combination of constant motion in the horizontal direction, and accelerated motion in the vertical direction. Therefore, the correct answer option is: D. constant, accelerated.
What is projectile motion?Projectile motion can be defined as a form of motion which is experienced by a physical object (body) that is projected near the surface of planet Earth, while moving along a parabolic (u-shaped curve) path, and under the influence of a gravitational force only.
Based on scientific research and records by scientists such as Galileo, we can infer and logically deduce that the initial horizontal velocity of a physical object undergoing a projectile motion is always equal to its final horizontal velocity.
Additionally, Galileo stated that projectile motion combines constant or uniform motion in the horizontal direction and accelerated motion in the vertical direction.
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A plane flies with an average
velocity of -98.5 m/s for 45.0 s.
What was its displacement?
(Unit = m)
Don't forget: velocities and displacements to
the right are +, to the left are -.
Answer:-4432.5 m
Explanation:trust
What is the phase angle between the voltages of the inductor and capacitor in a rlc series circuit?.
Answer: at least 180 degrees
a 65 kg bungee jumper drops from a 60 ledge. the bungee cord has an unstretched length of 20 m, meaning that for the first 20 m the only force on the jumper is gravity. the bungee cord acts like a linear spring. the jumper comes to rest 0.5 m above the surface of the water. what is the stiffness constant of the cord?
To find the stiffness constant of the cord, learn gravity and force.
What is gravity?
By means of gravity, a planet or other body pulls objects toward its center. All the planets are maintained in their orbits around the sun by the force of gravity.
What is force?
An object with mass changes its velocity in response to a push or pull. Force is an external agent that has the power to alter a body's resting or moving state. It has a size and a movement.
Enot=Eat start= Ug =mgh
=(65kg)(10m/s²)(60m)
=39,000J
Eat lowest point =Usp+Ug
=1/2K(Δy²)+mgh
=1/2k(39.5m)² + (65kg)(10m/s²)(0.5m)
from conservation of energy, solve to get K= 49.6N/m.
Therefore, the energy function can be written ( for y<40).
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PLS help confused. Will mark brainiest for the right answer.
Answer:
B
Explanation: You (with the ball in your hand)would move in the direction of the ball's initial motion. Momentum!
Answer: You would move backward.
Explanation: You would push back because you would move in the direction of the ball's initial motion. The ball's initial motion is to come toward you, so you would most likely move backward.
Let me know if this is right! :)
A van accelerates from a velocity of 2 m/s to a velocity of 20 m/s in 12 s.
Calculate the acceleration of the van.
Answer:
Explanation:
Given:
V₀ = 2 m/s
V = 20 m/s
Δt = 12 s
__________
a - ?
The acceleration of the van:
a = ΔV / Δt = (V - V₀) / Δt
a = (20 - 2) / 12 = 18 / 12 ≈ 1.5 m/s²
Calculator
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A speaker, rated at 4V, draws a current of 13A. It is left switched on for 3 seconds. How much electrical work is done on a speaker?
Answer:
16C
Explanation:
since current=CHARGE/TIME
THEREFORE CHARGE=TIME X CURRENT
=2X8
=16C
A heat engine operates between a source at 477°c and a sink at 25°c. If heat is supplied to the heat engine at a steady rate of 65,000 kj/min, determine the maximum power output of this heat engine.
T[tex]_{C}[/tex] = 25 + 273.15 = 298.15K
T[tex]_{H}[/tex] = 477 + 273.15 = 750.15K
And by replacing Carnot efficiency:
e = 1 - [tex]\frac{298.15}{750.15}[/tex] = 0.39475 = 39.47%
W[tex]_{max}[/tex] = e × Q[tex]_{H}[/tex] = 0.39475 × 65000[tex]\frac{KJ}{min}[/tex] = 25658.75 [tex]\frac{KJ}{min}[/tex]
How to calculate temperature?The United States (and its connected territories) and some Caribbean countries frequently use the Fahrenheit temperature scale, which bears the name of German physicist Daniel Gabriel Fahrenheit. Water freezes at 32°F and boils at 212°F according to the Fahrenheit scale (at sea level).
Nearly every other country uses the Celsius temperature scale, which was previously called centigrade before being changed for Swedish astronomer Anders Celsius. Water freezes at 0°C and boils at 100°C on the Celsius scale (at sea level).
For this case we can use the fact that the maximum thermal efficiency for a heat engine between two temperatures are given by the Carnot efficiency:
e = 1 - frac T[tex]_{C}[/tex]T[tex]_{H}[/tex]
We have on this case after convert the temperatures in kelvin this:
T[tex]_{C}[/tex] = 25 + 273.15 = 298.15K
T[tex]_{H}[/tex] = 477 + 273.15 = 750.15K
And replacing in the Carnot efficiency we got :
e = 1 - [tex]\frac{298.15}{750.15}[/tex] = 0.39475 = 39.47%
And the maximum power output on this case would be defined as:
W[tex]_{max}[/tex] = e × Q[tex]_{H}[/tex] = 0.39475 × 65000[tex]\frac{KJ}{min}[/tex] = 25658.75 [tex]\frac{KJ}{min}[/tex]
Where [tex]Q_{H}[/tex] represent the heat associated to the deposit with higher temperature
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three objects are at the top of an inclined plane: a disk, a sphere, and a ring. all of the objects have the same radius and the same mass. which object would finish last in a race down the incline if they are all released from rest? (hint: use conservation of energy methods, and note that at the bottom there is both translational and rotational energy)
The ring would finish at last in the race down the incline.
Incline is a a plane surface tilted at some angle from the horizontal.
The moment of inertia of the ring = [tex]mr^{2}[/tex]
The moment of inertia of the disc = ( [tex]mr^{2}[/tex] ) / 2
The moment of inertia of the solid sphere = 2( [tex]mr^{2}[/tex] ) / 5
Since the moment of inertia is the resistance to rotational motion, we see that the object with the smallest moment of inertia will reach the bottom first.
The gain in total kinetic energy is equal to the loss in gravitational potential energy, which in turn is the same for all the objects and is equal to 'mgh'
where h is the height of the inclined plane.
So the order of reaching the bottom is Sphere, disc and ring.
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he complex impedance of an electric circuit measures resistance as the real component and reactance as the imaginary component, both measured in ohms. what is the magnitude of impedance of an electric circuit with a resistance of 90 ohms and a reactance of 120 ohms?
The magnitude of impedance is 1.33 ohms .
What is meant by electric circuit?Electric circuit: a way for current to travel. A battery or generator, a device that provides energy to the charged particles that make up the current, a device that uses current, such as a lamp, an electric motor, or a computer, and the connecting wires or transmission lines make up an electric circuit.
Current flowing from the positive terminal to the negative terminal of the battery is known as an electric circuit. Putting together a circuit A cell or battery, connecting wires, a lightbulb, and a switch make up an electric circuit.
Given .
resistance = 90 ohms
reactance =120 ohms
So magnitude of impedance is 120/90
= 1.33 ohms
therefore the magnitude of impedance is 1.33 ohms
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explain how the sum of heat and work can be a state function, even though heat and work are themselves not state functions.
The system's internal energy change (E) must equal the sum of the heat transferred (q) and the work performed (w), as stated in the first law of thermodynamics: E = q + w..
Work and heat do not have a state function.
The first law of thermodynamics states that the change in a system's internal energy is equal to the total of heat and work.
ΔU = w+q
ΔU = modification of internal energy
q= heat
W= work
ΔU=qv
Accordingly, qv is a state function in this scenario since qv stands for q measured at constant volume.
additional circumstance steady pressure
W = pΔV
Work on the environment (expanding) or the surrounds is working on the system (compressing), which results in a new state function called ΔH and a change in enthalpy.
Heat is a change in energy rather than a quantity of energy that is contained because heat q is the amount of thermal energy that enters or exits the system throughout a process.
Work is another phrase for an energy transformation. the environment's good influence on the system or the environment's detrimental influence on the system ( negative)
The path functions q and w
However, q+w combined is a state function.
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at what frequency should a 200-turn, flat coil of cross sectional area of 300.0 cm2 be rotated in a uniform 30.0-mt magnetic field to have a maximum value of the induced emf equal to 8.0 v?
At 7.1 Hz a 200-turn, flat coil of cross sectional area of 300.0 cm2 be rotated in a uniform 30.0-mt magnetic field to have a maximum value of the induced emf equal to 8.0 v
What is magnetic field?An electric charge, an electric current, and magnetic materials are all affected magnetically by a magnetic field, which is a vector field. A force perpendicular to the magnetic field and its own velocity acts on a moving charge in a magnetic field.
Given,
number of turns is N = 200 turns
cross-sectional area is A = 300 cm² = 300 x 10⁻⁴ m²
the magnitude of magnetic field strength is B = 30 x 10⁻³ T
the maximum value of the induced emf is E = 8 V
Now,
Maximum induced emf is, E = NBAω
where,
ω is the angular velocity (ω = 2πf)
Now,
E = NBA2πf
where,
f is minimum frequency
So, f = E / (NBA2π)
f = 8 / (200 x 30 x 10⁻³ x 300 x 10⁻⁴ x 2 x 3.142)
f = 7.073 Hz
f = 7.1 Hz
∴ the minimum frequency of the coil is 7.1 Hz.
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Using the data collected from the motion detector, the group of students is
able to calculate both initial and final velocities. The initial velocity is
measured when the mass is released, and the final velocity is measured just
as the mass hits the floor. Using these velocities, they calculate the initial and
final kinetic energies. They also calculate the initial gravitational potential
energy by measuring the initial height when the mass is released. The final
gravitational potential energy is taken to be zero at the floor. When they
compare the final (kinetic) energy value to the initial energy value (that is, the
sum of the initial kinetic and gravitational potential energies), which of the
values is greater...
if the assumptions presented in the previous problem are true?
The initial and final energies a
if the assumptions presented in the previous problem are not true?
[ Select ]
Unless the above assumptions are clear, the initial and final energies are equal.
What is kinetic energy?Kinetic energy is the form of energy that an object or a particle possess due to its motion. If work, that transfers energy, is done on an object by applying a net force, the object accelerates and thereby gains kinetic energy. Kinetic energy is a property of a moving object or particle and depends on its motion as well as its mass. The type of motion may be translational (or motion along a path from one place to another), rotational, vibrational, or any combination of motions. Translational kinetic energy is one-half the product of its mass (m) and the square of its velocity (v) or 1/2mv².
Given,
Initial and final velocities = v₁ and v₂
Initial kinetic energy = [tex]\frac{1}{2} mv_{1} ^{2}[/tex]
Final kinetic energy = [tex]\frac{1}{2} mv_{2} ^{2}[/tex]
Gravitational potential energy is calculated = mgh
As the assumptions are not clear, this question assumes no air resistance. As a result, no energy is consumed by work.
then
Initial Kinetic Energy = Final Kinetic Energy
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if a falling ball made a perfectly elastic collision with the floor, would it rebound to its original height? explain.
When dumped, it would rebound all the way up to the original height.
What occurs when an impact is perfectly elastic?If there is no kinetic energy lost during contact, the collision is entirely elastic. In an inelastic collision, some of the kinetic energy is converted into another kind of energy during the contact.
The system's overall kinetic energy, which includes the interacting items, remains constant both before and after the impact. A very buoyant ball might serve as an illustration of an elastic collision. If you dropped it, it would return to its original height after bouncing all the way down.
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Use the diagram of the molecular structure of lactic acid to answer the question.
Which functional groups are represented in this molecular structure?
A) a methyl group, a hydroxyl group, and a carboxyl group
B) a sulfhydryl aroup. an amino group, and a carboxvl group
C) a methyl group, an amino group, and a carboxyl group
D) a sulfhydryl aroup, a hydroxvl group, and a carboxvl group
The functional groups that are represented in this molecular structure are; a methyl group, a hydroxyl group, and a carboxyl group
What are the functional groups?We know that the functional group would be defined as that atom, or a group of atoms or even a bond that is the major point where a chemical reaction occurs among the members of a particular hom----ologous series. Note that the hom----ologous series is a family of compounds that differ from each other by chain length only.
Now we have to look at the compound and of course the attachments to the compound would tell us how many of the functional groups that we do have in the molecule and we can take a cursory look at the image attached for this detail.
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what has more kinetic energy an object of mass 2m moving with speed 3v or an object of mass m moving with speed 4v
Kinetic energy The height of an object of mass m moving at speed 4v will be greater than that of an object of mass 2m moving at speed 3v. Kinetic energy = 0.5 m v2
A mass of 2 m moving at a speed of 3 v has kinetic energy of 9 m, while a mass of m moving at a speed of 4 v has kinetic energy of 8 m. The ability of an object to move another object is known as its kinetic energy. It is effective for a force to move an object. Furthermore, we are aware that an object in motion can cause a stationary object to move if it collides with it. It can therefore perform a function. The ability of an object to perform work as a result of its motion is how we define kinetic energy.
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Find the acceleration of a 10 kg bucket of water that is lifted with a force of 200 Newtons.
The acceleration of a 10 kg bucket of water that is lifted with a force of 200 Newtons is 20 N/kg.
The rate at which velocity changes with time, in terms of both speed and direction, is called acceleration.
Acceleration (a)
Mass (m) = 10 kg
Force (F) = 200 N or Newton
∴ a = F / m
=> a = 200 N / 10 kg
=> a = 20 N / kg
So, the acceleration of a 10 kg bucket of water that is lifted with a force of 200 Newtons is 20 N / kg.
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what conditions must occur for the two carts to move in different directions after the collision? (assuming that a moving cart collides elastically with a stationary cart).
As a result of the collision, the cart, which had a velocity of 1, comes to rest. The cart then accelerates with velocity v1 from rest. assuming that a moving cart collision elastically with a stationary cart.
We are aware that both the linear momentum and the kinetic energy are conserved in completely elastic velocity. However, only the kinetic energy of an inelastic impact is conserved. Any situation in which two or more bodies quickly exert forces on one other is referred to be a collision. The scientific definition of the word "collision" makes no reference to the magnitude of the force involved, despite the fact that the most frequent usage of the word relates to instances in which two or more objects clash violently.
The instantaneous speed could be compared to the speed shown by the speedometer.
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.
Which statement best shows that waves can carry energy?
Sounds can be recorded.
A rainbow shows a spectrum of colors.
You feel vibrations if loud sounds are played.
Light shining through some trees makes shadows.
The statement that best shows that waves can carry energy is option d: light shining through some trees makes shadows.
What is the most accurate way to define sound waves?A sound wave is the pattern of disruption brought on by the movement of energy moving through a medium as it propagates away from the source of the sound (such as air, water, or any other liquid or solid matter). Pressure waves are produced when an object vibrates, such as a ringing phone, and these waves are known as sound waves.
Therefore, note that the energy of a sound wave is transferred through particle contact. A vacuum cannot be traversed by a sound wave. Sound is now a mechanical wave as a result.
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What is the normal force acting on a 50kg dog? A)540N b)570N c)490N d)440N
Answer:
C) 490
Explanation:
Normal force = mass × gravitational acceleration
50kg × 9.8
490 N
how would the gravitational force of star james change if star james contracted to 1/7 of its previous diameter, without osing any of it's matter
The final gravitational force at the surface of the star is 49 times of the initial gravitational force.
Gravitational force definitions.The attraction that exists between all masses in the universe, particularly between the mass of the earth and objects that are close to its surface.
Use Newton's gravitational law to find the gravitational force at the surface of a star if the star contracted to one fifth of its previous diameter as follows.
Newton's gravitational law states that the gravitational force between two objects is inversely proportional to the square of their distance and directly proportional to the product of their masses.
[tex]F_g}[/tex] =GMm/r²
In this case, the two objects' masses are M and m, G is the gravitational constant, and r is their separation from one another.
Since mass is constant, the gravitational force at the surface of a star before contraction is,
F₁ =GMm/r₁²
Here, r₁ is initial diameter of the star.
The gravitational force at the surface of a star after the contraction is,
F₂ =GMm/r₂²
Here, r₂ is final diameter of the star.
Compare the equations, we get
F₂/F₁= GMm/r₂²/GMm/r₁²
F₂/F₁=(r₁/r₂)²
F₂ = F₁(r₁/r₂)²
Substitute r₁/7 for r₂ in equation and solve for final gravitational force on the star.
F₂ = F₁(r₁/r₁/7)²
F₂= 49F₁
Therefore, the final gravitational force at the surface of the star is 49 times of the initial gravitational force.
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Which of the following objects have kinetic energy?
An elephant walking 1.5 m/s along the ground.
A jet flying across the sky 4,000 m above the ground.
A car traveling 20 m/s along a flat road.
A concrete block sitting on the ground.
An apple on a tree branch 3.0 m above the ground.
if, in actuality, a 710-kg car with an initial speed of 114 km/h is observed to coast up a hill and stops at a height 25 m above its starting point, how much thermal energy was generated by friction in j?
The thermal energy was generated by friction is 180490.52J.
What is thermal energy?Molecules moving within an item or substance are referred to as thermally moving. The sun is the main source of thermal energy in our solar system, but every material possesses some form of thermal energy. Heat is a flow of thermal energy that occurs when energy is transferred from one substance or object to another.
Given,
Initial speed = 114km/h = 114000/3600 = 31.66 m/s
Height = 25m
[tex]E_{intial} = E_{final}[/tex]
mg[tex]y_{i}[/tex] + 1/2m[tex]v^{2} _{i{} }[/tex] = mg[tex]y_{f}[/tex] +1/2m[tex]v^{2} _{f{} }[/tex]
Solving [tex]y_{f}[/tex] we have,
[tex]y_{f}[/tex] = m(g[tex]y_{i}[/tex] + 1/2m[tex]v^{2} _{i{} }[/tex]-1/2m[tex]v^{2} _{f{} }[/tex])
[tex]y_{f}[/tex] = (0+ 1/2 (114×1000/60×60)²-0)/9.8
[tex]y_{f}[/tex] = h = 50.94m
loss of energy = mg (50.94 - 25)
loss of energy = 710× 9.8× 25.94
loss of energy = 180490.52J.
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Within free market economies, what role does self interest play? What role does competition play?
Economic activity is driven by self-interest, and competition helps to drive down costs and increase the quality, diversity, and creativity of goods and services.
What kind of activity is self-interested?Seeking your own personal gain is the definition of self-interest. You attend work in order to earn money to spend on the things you want. You attend school so that after you graduate, you'll be able to find a better career and get more money to spend on the things you desire.
How can self-interest be developed?Pick some fresh endeavors that promote goodwill in your career, family, and leisure life. Likewise, be adamant in your actions. When appropriate, communicate your thoughts and feelings to others by asking for what you want, declining what you don't want, and saying No to requests. For a while, make it a point to treat yourself to something every day.
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