Average acceleration is the change in velocity with time.
Acceleration takes place when velocity changes with time. Velocity being a vector quantity may change in magnitude or direction any of the change results to acceleration
The pace at which a body's velocity varies is represented by average acceleration, which is a vector quantity.
What is average acceleration?The rate of change of velocity with respect to time is known as acceleration. According to Newton's second law, the eventual effect of all forces applied to a body is its acceleration.
The formula for acceleration is;
[tex]\rm a = \frac{v-u}{t}[/tex]
u is the initial speed
v is the final speed
t is the time interval
a is the acceleration of ball
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What is involved when water changes from one phase to the next?
a
thermal energy
b
indirect energy
c
finite energy
d
ideal gas laws
Thermal energy is involved when water changes from one phase to the next. Option A is correct.
What is latent heat ?Latent heat is the heat needed for the phase change . When the temperature remains constant during melting or boiling, the added energy is employed in the phase change process.
The total number of water particles remains constant when water changes states throughout the water cycle.
When water alterations from one phase to the next, thermal energy is involved. Latent heat is the storage of thermal energy.
Hence, option A is correct.
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the connection between a medium and a mechanical wave
Answer:
The energy of a mechanical wave can travel only through matter. The matter through which the wave travels is called the medium (plural, media). The medium in the water wave pictured above is water, a liquid. But the medium of a mechanical wave can be any state of matter, even a solid.
Explanation:
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A metal bar is in the xy-plane with one end of the bar at the origin. a force f⃗ =( 6.88 n )i^+( -2.62 n )j^ is applied to the bar at the point x= 2.88 m , y= 3.70 m .
A metal bar is in the xy-plane with one end of the bar at the origin, [tex]\[r = (3.87 \, \text{m}) \mathbf{i} + (3.21 \, \text{m}) \mathbf{j}\][/tex], [tex]\theta\approx 55.16^\circ\][/tex], magnitude of torque is 22.58 Nm.
a) Position Vector r can be calculated as:
Given:
[tex]\(x = 3.87 \, \text{m}\)[/tex]
y = 3.21 m
The position vector r for the point where the force is applied is:
[tex]\[r = (3.87 \, \text{m}) \mathbf{i} + (3.21 \, \text{m}) \mathbf{j}\][/tex]
b) Magnitude of Torque can be calculated as:
Magnitude of r:
[tex]\[|r| = \sqrt{(3.87 \, \text{m})^2 + (3.21 \, \text{m})^2} \approx 5.019 \, \text{m}\][/tex]
Magnitude of F:
[tex]\[|F| = \sqrt{(6.82 \, \text{N})^2 + (-3.24 \, \text{N})^2}\\\\ \approx 7.610 \, \text{N}\][/tex]
Calculate the dot product of r and F:
[tex]\[r \cdot F = (3.87 \, \text{m}) (6.82 \, \text{N}) + (3.21 \, \text{m}) (-3.24 \, \text{N})\\\\ \approx 16.658 \, \text{N} \cdot \text{m}\][/tex]
Calculate the angle [tex]\(\theta\)[/tex] using the dot product and magnitudes:
[tex]\[\cos(\theta) = \frac{r \cdot F}{|r| \cdot |F|} \\\\= \frac{16.658 \, \text{N} \cdot \text{m}}{(5.019 \, \text{m})(7.610 \, \text{N})}\\\\ \approx 0.5526\][/tex]
[tex]\[\theta \approx \cos^{-1}(0.5526)\\\\ \approx 55.16^\circ\][/tex]
Now calculate the magnitude of the torque using the sine of the angle:
[tex]\[|\tau| = |r| \cdot |F| \cdot \sin(\theta)\\\\ = (5.019 \, \text{m}) (7.610 \, \text{N}) \sin(55.16^\circ)\\\\ \approx 22.58 \, \text{N} \cdot \text{m}\][/tex]
c) Direction of Torque:
According to the right-hand rule, the torque points either into or out of the plane formed by r and F. Its direction is perpendicular to that plane. The sign of the angle determines the precise orientation.
In this case, since [tex]\(\theta \approx 55.16^\circ\)[/tex] is positive (counterclockwise rotation), the torque points out of the plane formed by r and F.
Thus, the direction of the torque is outward from the xy-plane.
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Your question seems incomplete, the probable complete question is:
A metal bar is in the xy-plane with one end of the bar at the origin. A force F=(6.82)i+ -3.24j is applied to the bar at the point x=3.87m , y=3.21m .
What is the position vector r for the point where the force is applied?
a Express your answer in terms of the unit vectors i and j .
b What are the magnitude of the torque with respect to the origin produced by F?
c What are direction of the torque with respect to the origin produced by F?
A student measures the voltage and current between two points in an
electrical circuit. If the voltage is 120 V and the current is 0.5 A, what is the
resistance, according to Ohm's law?
A. 0.00402
Β. 240 Ω
C. 1200
D. 60.00
Answer:
B. 240Ω
Explanation:
The formula between voltage, current and resistance is:
voltage = current × resistance
So resistance = voltage ÷ current
Therefore resistance = 120 ÷ 0.5
Resistance = 240Ω
If a runner exerts 457 j of work to make 321 w of power then how long did it take the runner to do the work
The time taken by the runner to do the work is 1.42 seconds.
Given the data in the question;
Work done; [tex]W = 457J[/tex]Power; [tex]P = 321W[/tex]Time elapsed; [tex]t = \ ?[/tex]PowerPower can be simply referred to as the quantity of energy transferred per unit time.
It is expressed as;
[tex]P = \frac{W}{t}[/tex]
Where W is work done and t is time elapsed.
To determine the time it took the runner to do the work, we substitute our given values into the expression above.
[tex]P = \frac{W}{t} \\\\t = \frac{W}{P} \\\\t = \frac{457J}{321W} \\\\t = \frac{457 kgm^2/s^2}{321 kgm^2/s^3}\\\\t = 1.42s[/tex]
Therefore, the time taken by the runner to do the work is 1.42 seconds.
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Which force counteracts motion whenever two surfaces come into contact?.
Answer:
crush
Explanation:
because the body come into contact
Prelab exercise 1. Why is it important for your measurements that the track is level?
It is very important for your measurements that the track is level because unlevel track change the acceleration of an object.
Why track's level is important?A non-level track leads to bring change in the acceleration of an object which leads to different value of experiment.
So we can conclude that it is important for your measurements that the track is level because unlevel track change the acceleration of an object.
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The track must be level for your measurements because an unlevel track changes the acceleration of an object.
What is measurement?It is defined as the numerical quantity that gives an idea about object length, width, and many more. It can be used to compare two objects.
The non-level track causes changes in an object's acceleration, resulting in various experiment values.
As a result, we can deduce that now the levelness of the track is critical for your measurements, as an uneven track changes an entity's acceleration.
Thus, the track must be level for your measurements because an unlevel track changes the acceleration of an object.
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You research your favorite topic: earthquakes. You build a tall LEGO building, and you want to know which type of motion is most damaging to your building. You discover in your research that side-to-side motion is the worst. You will place the building on a piece of wood and shake it for durations of 30 seconds, 60 seconds, and 90 seconds. You will try an up-and-down motion and side-to-side motion.
Answer:
If the Lego building is shaken side to side, it will withstand up to 60 seconds because front to back will cause the top of the building to collapse.
Which reaction connects the citric acid cycle to the electron‑transport chain and amino acid synthesis?
Conversion of succinylcoA to succinate is the reaction that link acid cycle to the electron‑transport chain and amino acid synthesis.
Conversion of succinylcoA to succinateSuccinylCoA is converted into succinate through the hydrolytic release of coenzyme A by succinyl-CoA synthetase Also succinyl-CoA is porphyrin synthesis, where it combine with glycine by ALA synthase to form δ-aminolevulinic acid.
Succinyl CoA is catalytically converted to succinate. The enzyme stimulates the hydrolysis of succinyl CoA into succinate and ATP and this represents a remarkable point of substrate level phosphorylation. After this, it link up to the electron transport chain via citric acid cycle.
Therefore, Conversion of succinylcoA to succinate is the reaction that link citric acid cycle to the electron‑transport chain and amino acid synthesis.
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The electron‑transport chain reaction connects the citric acid cycle to the electron‑transport chain and amino acid synthesis.
What is an electron‑transport chain reaction?The electron transport chain is a set of protein complexes that link redox processes to create an electrochemical potential that leads to the production of ATP in a process known as
Both photosynthesis and cellular respiration occur in mitochondria.
As a result, the process that connects the citric acid cycle to the electron transport chain and amino acid synthesis is succinyl-CoA to succinate conversion.
Hence the electron‑transport chain reaction connects the citric acid cycle to the electron‑transport chain and amino acid synthesis.
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Consider the following processes: The temperature of two identical gases are increased from the same initial temperature to the same final temperature. Reversible processes are used. For gas A the process is carried out at constant volume while for gas B it is carried out at constant pressure. The change in entropy:_________.
i. is greater for B
ii. is the same for A and B
iii. is greater for A only if the initial temperature is high
iv. is greater for A
v. is greater for A only if the initial temperature is low
The entropy at constant pressure is always greater than that at constant volume and the change in entropy for the two processes is greater for gas B.
Second law of thermodynamicsAccording to the second law of thermodynamics, entropy in the isolated system always stays the same or increases.
Since gas does work in isobaric (constant pressure) change processes, the entropy at constant pressure will be greater than that at constant volume.
Thus, for gas A the process is carried out at constant volume while for gas B that is carried out at constant pressure. The change in entropy is greater for gas B.
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What best describes the motion of the medium particles in a longitudinal wave? The medium does not move. The medium moves in all directions. The medium vibrates as it moves in a circular path around the wave. The medium vibrates parallel to the direction of the wave.
In the motion of the medium particles in a longitudinal wave, the medium vibrates parallel to the direction of the wave.
What is a longitudinal wave?A longitudinal wave is a wave that is transversing along the length. When the displacement of medium and travel of wave is the same in that condition wave is known as the longitudinal wave.
It requires some medium to travel. A mechanical and sound wave is an example of a longitudinal wave.
Hence in the motion of the medium particles in a longitudinal wave, the medium vibrates parallel to the direction of the wave.
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Answer:
d the medium vibrates parallel to the direction of the wave.
Explanation:
Consider a system consisting of three particles: m1 = 4 kg, vector v1 = < 10, -5, 15 > m/s, m2 = 9 kg, vector v2 = < -15, 5, -3 > m/s, m3 = 3 kg, vector v3 = < -24, 36, 18 > m/s.
a) what is the total momentum of this system?
b) what is the velocity of the center of mass of this system?
c) what is the total kinetic energy of this system?
d) what is the translational kinetic energy of this system?
e) what is the kinetic energy of this system relative to the center of mass?
one way to calculate krel is to calculate the velocity of each particle relative to the center of mass, by subtracting the center-of-mass velocity from the particle's actual velocity to get the particle's velocity relative to the center of mass, then calculating the corresponding kinetic energy, then adding up the three relative kinetic energies. however, there is a much simpler way to determine the specified quantity, without having to do all those calculations; think about what you know about the relationships among the various kinds of kinetic energy in a multiparticle system.
The answers to your questions are as listed below
A) The total momentum of the system is : < - 167, 133, 87 > kg m/s
B) Velocity of the center of mass of this system : < - 10.44 , 8.31, 5.44 > m/s
C) Total kinetic energy of the system : 5159.5 J
D) Translational kinetic energy of the system : 1660.84 J
E) kinetic energy relative to the center of mass : 3498.66 J
Given data :
m₁ = 4 kg , V₁ = < 10, -5, 15 > m/s
m₂ = 9 kg, V₂ = < -15, 5, -3 > m/s
m₃ = 3 kg V₃ = < -24, 36, 18 > m/s.
A) Determine the total momentum of the systemTotal momentum = Σ mv
= < 4*10 + 9*(-15) + 3*(-24), 4*(-5) + 9*5 + 3*36, 4*15 + 9 (-3) + 3*18 >
= < - 167, 133, 87 > kg m/s
B) Velocity at the center of mass of this systemVelocity = < - 167 / 16 , 133/ 16, 87/ 16 >
= < - 10.44 , 8.31, 5.44 > m/s
C) Determine the total kinetic energy of the systemTotal Kinetic energy = 1/2 m₁v₁² + 1/2 m₂v₂² + 1/2 m₃v₃² --- ( 1 )
where : v² = v₁² + v₂² + v₃²
therefore
Total kinetic energy = 700 + 1165.5 + 3294
= 5159.5 J
D) Determine the translational kinetic energy of the system
Translational kinetic energy ( Kcm ) = 1/2 ( m₁ + m₂ + m₃ ) * Velocity²
= 1/2 ( 16 ) * ( - 10.44² + 8.31² + 5.44² )
Hence translational kinetic energy = 1660.84 J
E) The Kinetic energy of the system relative to the center of mass
Krel = Ktotal - Kcm
= 5159.5 - 1660.84
= 3498.66 J
Hence we can conclude that the answers to your questions are as listed above.
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Suppose that two point charges, each with a charge of 1 coulomb are separated by a distance of 1 meter. Determine the magnitude of the electrical force between them
The magnitude of the electrical force between the two identical electrical charges is 8.98755 × 10⁹N.
Given the data in the question;
Single charge each with; [tex]q_1\ and\ q_2[/tex] [tex]= 1C[/tex]Distance between; [tex]r = 1m[/tex]Electric force between; [tex]F = \ ?[/tex]Coulomb's lawCoulomb's law states "that the force between two electrical charges is directly proportional to the product of the charges and inversely proportional to the square of the distance between them".
It is expressed as;
[tex]F = k\frac{q_1q_2}{r^2}[/tex]
Here, [tex]q_1\ and\ q_2[/tex] are the two electrical charges, r is the distance between them and k is the Coulomb constant ( [tex]k = 8.98755*10^9 kgm^3/s^2C^2[/tex])
To determine the electrical force between the two charges, we substitute our values into the expression above.
[tex]F = k\frac{q_1q_2}{r^2}\\\\F = (8.98755*10^9 kgm^3/s^2C^2)*\frac{(1C)(1C)}{(1m)^2}\\\\F = (8.98755*10^9 kgm^3/s^2C^2)*\frac{1C^2}{1m^2}\\\\F = 8.98755*10^9 kgm/s^2\\\\F = 8.98755*10^9 N[/tex]
Therefore, the magnitude of the electrical force between the two identical electrical charges is 8.98755 × 10⁹N.
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The magnitude of the electrical force between the two charges is 8.987×10⁹ N.
What is coulomb's law?As per the coulomb's law, the electrical force between any two charges separated by a distance of r is given by the formula,
[tex]F = k\dfrac{q_1q_2}{r^2}[/tex]
Given that the value of q₁ and q₂ is 1 coulomb, while the distance between them is 1 meter. Also, the value of k is 8.987×10⁹ N·m²·C⁻², therefore, the force can be written as,
[tex]F = k\dfrac{q_1q_2}{r^2}\\\\F = (8.987 \times 10^{9}) \times (\dfrac{1 \times 1}{1^2})\\\\F= 8.987 \times 10^{9}\rm\ N[/tex]
Hence, the magnitude of the electrical force between the two charges is 8.987×10⁹ N.
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When a skydiver falls towards the Earth, the force of gravity from Earth pulls her towards the
Earth and she is obviously accelerating towards the Earth.
Can the reverse (the force of gravity pulls the Earth towards her and the Earth is accelerating
towards her) be true? Explain.
Answer:
yes
true
Explanation:
because earth is rotation
How many ounces in a cup?
Answer:
8 oz
Explanation:
You’ll start by investigating how earth’s surface temperature varies. open my nasa data, and click on data set in the top left corner of the page. within the atmosphere category, select all data, then select temperature. now, select monthly air surface temperatures. after the new map appears on your screen, select the animate option near the top of the page, and then select ok to see the animation. set the time range on the animation for the most recent five years, and then click submit. you can control the speed of the animation with the controls beneath the map.
question 1
describe patterns you observe in earth’s surface temperature. how do these patterns change during the course of a year and from year to year? use lines of latitude and degrees celsius in your description.
Different patterns we observe in earth’s surface temperature due to angle, distance from the sun, latitude of the place and ocean currents.
Describe patterns you observe in earth’s surface temperature?The Earth's surface experiences a range of temperature due to different conditions such as angle of the sun, distance from the sun, the latitude of the place, distance from the sea, altitude of the place and ocean currents.
So we can conclude that different patterns we observe in earth’s surface temperature due to angle, distance from the sun, latitude of the place and ocean currents.
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A runner begins from rest at the starting line and travles for 6.5 seconds, a runner reaches a speed of 13.4 m/s what is the runners acceleration?
The acceleration of the runner in the given time is 2.06m/s².
Given the data in the question;
Since the runner begins from rest,
Initial velocity; [tex]u = 0[/tex]Final velocity; [tex]v = 13.4m/s[/tex]Time elapsed; [tex]t = 6.5s[/tex]Acceleration of the runner; [tex]a = \ ?[/tex]
Velocity is the speed at which an object moves in a particular direction.
Acceleration is simply the rate of change of the velocity of a particle or object with respect to time. Now, we can see the relationship from the First Equation of Motion
[tex]v = u + at[/tex]
Where v is final velocity, u is initial velocity, a is acceleration and t is time elapsed.
To determine the acceleration of the runner, we substitute our given values into the equation above.
[tex]v = u + at\\\\13.4m/s = 0 + (a * 6.5s)\\\\13.4m/s = a * 6.5s\\\\a = \frac{13.4m/s}{6.5s}\\ \\a = 2.06m/s^2[/tex]
Therefore, the acceleration of the runner in the given time is 2.06m/s².
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13. A mass of 1 kg undergoes simple harmonic motion with amplitude of 1 m. If the period of the oscillation is 1 s, calculate the internal energy of the system.
Please show all of your work.
first we need omega
T=1sHence
[tex]\\ \rm\rightarrowtail \omega=\dfrac{2\pi}{T}=2\pi[/tex]
Now
Total energy:-
[tex]\\ \rm\rightarrowtail \dfrac{1}{2}m\omega ^2A^2[/tex]
[tex]\\ \rm\rightarrowtail \dfrac{1}{2}(1)(2\pi)^2(1)^2[/tex]
[tex]\\ \rm\rightarrowtail \dfrac{1}{2}(4\pi ^2[/tex]
[tex]\\ \rm\rightarrowtail 2\pi ^2[/tex]
[tex]\\ \rm\rightarrowtail 2(3.14)^2[/tex]
[tex]\\ \rm\rightarrowtail 19.72J[/tex]
Assume that a gravitational anomaly in the solar system has shifted a field of asteroids into Earth’s orbit, and the field is now moving directly towards Earth. The asteroid field has a density of rho (asteroids/volume), and each asteroid has an average mass of m. The asteroid field stretches over a distance d in Earth’s path. Assume that the Earth moves with a velocity of v, the asteroids with u, and that be the radius of the Earth. The Earth collides with the asteroid field:
Show that the slow-down ∆v of the Earth due to the asteroid collisions is given by:
Answer:
An asteroid is a minor planet of the inner Solar System. Historically, these terms have been applied to any astronomical object orbiting the Sun.
What is the direction of the normal contact force of the road on the wheels?
Tick one box.
Down
Left
Right
Up
The direction of the normal contact force of the road on the wheels is : ( B ) Left
Contact force
The contact force of the road on the wheels will act in a direction opposite to the movement of the wheel on the road. therefore as the wheel moves forward ( right ), the contact force will move backwards ( left ) of the direction of motion.
Hence we can conclude that the direction of the normal contact force of the road on the wheels is : ( B ) Left
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1. A temperature unit is known as a
Explanation:
i think is per the International System of Units is Kelvin which is represented by the symbol K.
Which statement explains how the charges on objects determine the electric force between them? (1 point)
O Objects with positive charges repel each other, and objects with negative charges attract each other
O Objects with the same charge attract each other, and objects with opposite charges repel each other
O Objects with positive charges attract each other, and objects with negative charges repel each other.
O Objects with the same charge repel each other, and objects with opposite charges attract each other
Objects with the same charge repel each other, and objects with opposite charges attract each other
Effect of similar charges on each otherAccording to Coulomb, the electric force for charges at rest has the following properties: Like charges repel each other; unlike charges attract. Thus, two negative charges repel one another, while a positive charge attracts a negative charge. The attraction or repulsion acts along the line between the two charges.
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The kinetic energy of a javelin is 81 J, and its speed is 9.0 m/s. What is its mass?
A. 0.5 kg
B. 1.0 kg
C. 2.0 kg
D. 9.0 kg
Answer:
2 kg
Explanation:
K.E. = 1/2 m v^2
81 = 1/2 m (9^2)
1 = 1/2 m
m = 2 kg
Use work and energy to find an expression for the speed
of the block in the following figure just before it hits the
floor.(Figure 1)
Since the kinetic energy is equal to the potential energy then the speed of the object is √2gh.
Work and energyThe term work refers to the product of force and distance moved by force while energy is the ability to do work. The question is incomplete as the figure is not shown.
We know that the kinetic energy is equal to the potential energy hence;
mgh = 1/2mv^2
gh= 1/2v^2
v = √2gh
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What happens to force when two charges move away?
If the distance between the two charges is doubled, the attraction or repulsion becomes weaker.
Explanation:
If you wanted to melt ice, then heat it up, and get the water to just barely vaporize, how many equations would you need to solve for the energy used in this procedure?
Two equations will be needed to solve for the energy used in this procedure.
What is Energy?This is defined as the ability or capacity to do work. Ice being converted to vapor requires energy and the equations are seen below:
H₂O₍s₎ ⇒ H₂O₍l₎
H₂O₍l₎ ⇒ H₂O₍g₎
These are the equations which are used to calculate energy with heat being involved in both reactions.
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The physical meaning of 220 volts
Answer:
a particular level of electical potential from a power source
A softball and a basketball start from rest and roll down an incline. Which ball reaches the bottom first?
Answer:
both
Explanation:
gravity is the same for both
A ball rolls down an inclined plane, starting from rest. if the total time it takes to reach the end of the inclined plane is t, how much time has elapsed when it is halfway down the incline 0.5t
An inclined plane is a straightforward device with a sloping surface that is used to lift heavy objects. When friction is taken into account, the force needed to move an object up an incline is less than the weight being raised. The needed force is closer to the real weight the higher the slope or incline.
The inclined plane is the most basic of all simple machines because nothing needs to move for it to function. In order to save effort, you have to move objects farther when using an inclined plane. A variety of techniques can be used to create an inclined plane. It can be as simple as a log leaning against a tree in the woods or a piece of wood placed on the edge of a stair.
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3. Describe comets and their orbits in the solar system.
Comets have an extremely eccentric orbit around the Sun. They can travel hundreds of thousands of years through the solar system before returning to the Sun at perihelion. Comets, like all orbiting bodies, obey Kepler's Laws, which state that the closer they get to the Sun, the faster they move.
A comet is a dirty snowball many kilometers across that exists at a considerable distance from the Sun. However, when it gets closer to the Sun, the comet's surface warms up, causing its components to melt and vaporize, resulting in the comet's distinctive tail. The distance between the Earth and the Sun can be measured in comet tails.
A sound wave passes from air into water and then into steel. With each change in medium, what happens to the speed of the wave?.
Answer:
Explanation:
You need to consider the index of refraction.
index of refraction of air: 1.00
index of refraction of water: 1.33
Index of refraction of steel: 2.75681
If the sound wave passed from air into water, it passes from a lower index to a higher index of refraction.
As the wave travels into the more dense medium (higher n), it slows down. Therefore from air to water (lower to higher) it slows down, and from water to steel (n of steel is higher that n of water) therefore it slows down even more.