Question 1

Two cars start at the same point,but travel in opposite directions on a circular path of radius R,each at speed v.While each car travels a distance less than 
,one quarter circle,the center of mass of the two cars

Accepted Answer

The answer of Two cars start at the same point,but...

Question 2

Two bodies of equal mass m collide and stick together.The quantities that always have equal magnitude for both masses during the collision are

Accepted Answer

During a collision, the total momentum of the system is conserved. Since the masses are equal, their individual changes in momentum will also be equal in magnitude. Therefore, (a) is true. 
According to Newton's third law, for every action, there is an equal and opposite reaction. When the two masses collide, they exert equal and opposite forces on each other. Therefore, (b) is also true. 
However, during an inelastic collision (when the two masses stick together), the total kinetic energy of the system is not conserved. The kinetic energy before the collision is divided between both masses as mechanical energy, which is released as heat or other forms of energy after the collision. Therefore, (c) is not true. 
Hence, the correct answer is (E) only (a) and (b) above.

Question 3

If you know the impulse that has acted on a body of mass m you can calculate

Accepted Answer

The answer of If you know the impulse that has...

Question 4

A ball falls to the ground from height h and bounces to height h'.Momentum is conserved in the ball-earth system

Accepted Answer

Momentum is always conserved in the ball-earth system regardless of the height h' the ball reaches after bouncing. This is because the law of conservation of momentum applies to all interactions, assuming no external forces act on the system.

Question 5

When two bodies of different masses collide,the impulses they exert on each other are

Accepted Answer

According to Newton's third law of motion, when two bodies of different masses collide, they exert equal and opposite forces on each other. Therefore, the impulses they exert on each other are also equal and opposite. This is true for all collisions, whether elastic or inelastic. Therefore, option B is the correct choice.

Question 6

Two boys in a canoe toss a baseball back and forth.What effect will this have on the canoe? Neglect (velocity-dependent)frictional forces with water or air.

Accepted Answer

The canoe and the boys will experience equal and opposite forces from the ball each time it is thrown. This will cause the canoe to oscillate back and forth, always moving in the opposite direction of the ball because of the conservation of momentum. However, since there are two boys in the canoe and they are both throwing the ball, the oscillation may be more complex and erratic.

Question 7

A ball of mass m_B is released from rest and acquires velocity of magnitude v_B before hitting the ground.The ratio of the kinetic energy the Earth acquires to the kinetic energy the ball acquires is

Accepted Answer

The kinetic energy of the ball just before it hits the ground is given by (1/2)mv^2, where m is the mass of the ball and v is its velocity. The kinetic energy of the Earth is given by (1/2)MEv^2, where ME is the mass of the Earth. Since the ball is much lighter than the Earth, it acquires much more kinetic energy than the Earth does. The ratio of the kinetic energy of the Earth to that of the ball is (1/2)MEv^2 / (1/2)mv^2 = (ME/m), which is much greater than 1. Therefore, the correct answer is C.

Question 8

An exam paper contains the following equation for rocket propulsion: ) The error in the equation is that,instead of (v + v_e),the velocity of the fuel relative to the ground should be

Accepted Answer

The correct equation should be (v - v_e), as the velocity of the fuel relative to the ground should be subtracted from the velocity of the rocket. Option A is the opposite sign of the correct answer, option B adds the two velocities instead of subtracting them, option D subtracts the rocket velocity from the fuel velocity instead of the other way around, and option E multiplies the fuel velocity by 2 for no reason. Only option C correctly subtracts the fuel velocity from the rocket velocity.

Question 9

Stan argues that momentum cannot be conserved when a collision is not a head-on collision.Rachel insists it is conserved because each body receives an impulse of equal magnitude.Rachel is correct because

Accepted Answer

Rachel's argument is supported by all the given reasons: A) Newton's third law ensures that forces between the two bodies are equal and opposite, B) these forces act for the same amount of time, and C) the conservation of momentum is indeed a vector equation, meaning it applies in all directions, not just for head-on collisions.

Question 10

When the rate of burn and the exhaust velocity are constant,a rocket ascends with

Accepted Answer

The answer of When the rate of burn and the...

Question 11

An astronaut outside a spaceship hammers a loose rivet back in place.What happens to the astronaut as he swings the hammer?

Accepted Answer

This is due to Newton's third law of motion. When the astronaut pulls the hammer back, they exert a force on the hammer towards themselves, causing a reaction force that moves them towards the spaceship. When they swing the hammer forward, the opposite occurs: they exert a force on the hammer away from themselves, and the reaction force moves them away from the spaceship.

Question 12

In an elastic collision between two bodies of mass m₁ and m₂,with m₂ initially at rest,mass 1 moves off at angle θ relative to the direction of its initial velocity and mass 2 at angle φ.An exam paper shows the equations below: M₁v₁_i0 = m₁v₁_f cosθ + m₂v₂_f sinφ = m₁v₁_f sinθ + m₂v₂_f cosφ What error(s)has the student made?

Accepted Answer

Both equations contain errors. In the first equation, the term m₂v₂_f sinφ should be m₂v₂_f cosφ, as the angle associated with mass 2 is given as φ, which is the angle at which it moves relative to its initial velocity direction. Similarly, in the second equation, the term m₂v₂_f cosφ should be m₂v₂_f sinφ. Additionally, in the second equation, the plus sign between the terms on the right should be a minus sign. Therefore, the correct answer is D, all of the errors listed above.

Question 13

A ball of mass m_B is released from rest and acquires velocity of magnitude v_B before hitting the ground.The ratio of the impulse delivered to the Earth to the impulse delivered to the ball is

Accepted Answer

The answer of A ball of mass m_B is released...

Question 14

Exhibit 9-1
Two birds of prey hurtling after the same mouse collide in mid-air and grab each other with their talons.Each 250-g bird is flying at 30 m/s at a 60° angle to the ground.  Use this exhibit to answer the following question(s).
-Refer to Exhibit 9-1.What is the magnitude of their velocity,in m/s,immediately after the collision?

Accepted Answer

The answer of Exhibit 9-1
Two birds of prey hurtling after...

Question 15

The value of the momentum of a system is the same at a later time as at an earlier time if there are no

Accepted Answer

The value of the momentum of a system remains constant (is conserved) if there are no external forces acting on the system. This is a direct consequence of Newton's third law of motion and the principle of conservation of momentum. Internal forces, regardless of their nature (collisional or non-collisional), do not change the total momentum of the system; it is the external forces that can change the system's total momentum.

Question 16

The law of conservation of momentum applies to a collision between two bodies since

Accepted Answer

The law of conservation of momentum is based on Newton's third law, which states that for every action, there is an equal and opposite reaction. This means that in a collision, the two bodies exert equal and opposite forces on each other, ensuring that the total momentum before the collision is equal to the total momentum after the collision.

Question 17

A ball of mass m_B is released from rest and acquires velocity of magnitude v_B before hitting the ground.The ratio of the magnitude of the momentum the Earth acquires to the magnitude of the momentum the ball acquires is

Accepted Answer

The answer of A ball of mass m_B is released...

Question 18

Exhibit 9-1
Two birds of prey hurtling after the same mouse collide in mid-air and grab each other with their talons.Each 250-g bird is flying at 30 m/s at a 60° angle to the ground.  Use this exhibit to answer the following question(s).
-Refer to Exhibit 9-1.What is the magnitude of their total momentum,in 
,immediately after the collision?

Accepted Answer

The answer of Exhibit 9-1
Two birds of prey hurtling after...

Question 19

In an elastic collision between two bodies of equal mass,with body 2 initially at rest,body 1 moves off at angle θ relative to the direction of its initial velocity and body 2 at angle φ.The sine of the sum of θ and φ,sin(θ + φ),is equal to

Accepted Answer

The answer of In an elastic collision between two bodies...

Question 20

A steel ball bearing of mass m₁ and speed of magnitude v₁ has a head-on elastic collision with a steel ball bearing of mass m₂ at rest.Rank the speed v₁ of m₁ relative to v₂,the magnitude of the speed of m₂,after the collision when i.m₁ > m₂;ii)m₁ = m₂;and iii)m₁ < m₂.

Accepted Answer

In an elastic collision, the total kinetic energy and momentum are conserved. When m1 > m2, m1 will have a smaller speed after the collision (v1 < v2) to conserve momentum. When m1 = m2, both objects will have the same speed after the collision (v1 = v2). When m1 < m2, m1 will have a larger speed after the collision (v1 > v2) to conserve momentum.

Quiz 9: Linear Momentum and Collisions

Two cars start at the same point,but travel in opposite directions on a circular path of radius R,each at speed v.While each car travels a distance less than ,one quarter circle,the center of mass of the two cars

Two bodies of equal mass m collide and stick together.The quantities that always have equal magnitude for both masses during the collision are

If you know the impulse that has acted on a body of mass m you can calculate

A ball falls to the ground from height h and bounces to height h'.Momentum is conserved in the ball-earth system

When two bodies of different masses collide,the impulses they exert on each other are

Two boys in a canoe toss a baseball back and forth.What effect will this have on the canoe? Neglect (velocity-dependent) frictional forces with water or air.

A ball of mass m_B is released from rest and acquires velocity of magnitude v_B before hitting the ground.The ratio of the kinetic energy the Earth acquires to the kinetic energy the ball acquires is

An exam paper contains the following equation for rocket propulsion: ) The error in the equation is that,instead of (v + v_e) ,the velocity of the fuel relative to the ground should be

Stan argues that momentum cannot be conserved when a collision is not a head-on collision.Rachel insists it is conserved because each body receives an impulse of equal magnitude.Rachel is correct because

When the rate of burn and the exhaust velocity are constant,a rocket ascends with

An astronaut outside a spaceship hammers a loose rivet back in place.What happens to the astronaut as he swings the hammer?

A ball of mass m_B is released from rest and acquires velocity of magnitude v_B before hitting the ground.The ratio of the impulse delivered to the Earth to the impulse delivered to the ball is

The value of the momentum of a system is the same at a later time as at an earlier time if there are no

The law of conservation of momentum applies to a collision between two bodies since

A ball of mass m_B is released from rest and acquires velocity of magnitude v_B before hitting the ground.The ratio of the magnitude of the momentum the Earth acquires to the magnitude of the momentum the ball acquires is

In an elastic collision between two bodies of equal mass,with body 2 initially at rest,body 1 moves off at angle θ relative to the direction of its initial velocity and body 2 at angle φ.The sine of the sum of θ and φ,sin(θ + φ) ,is equal to

A steel ball bearing of mass m₁ and speed of magnitude v₁ has a head-on elastic collision with a steel ball bearing of mass m₂ at rest.Rank the speed v₁ of m₁ relative to v₂,the magnitude of the speed of m₂,after the collision when i.m₁ > m₂;ii) m₁ = m₂;and iii) m₁ < m₂.

Quiz 9: Linear Momentum and Collisions

Two cars start at the same point,but travel in opposite directions on a circular path of radius R,each at speed v.While each car travels a distance less than ,one quarter circle,the center of mass of the two cars

Two bodies of equal mass m collide and stick together.The quantities that always have equal magnitude for both masses during the collision are

If you know the impulse that has acted on a body of mass m you can calculate

A ball falls to the ground from height h and bounces to height h'.Momentum is conserved in the ball-earth system

When two bodies of different masses collide,the impulses they exert on each other are

Two boys in a canoe toss a baseball back and forth.What effect will this have on the canoe? Neglect (velocity-dependent) frictional forces with water or air.

A ball of mass mB is released from rest and acquires velocity of magnitude vB before hitting the ground.The ratio of the kinetic energy the Earth acquires to the kinetic energy the ball acquires is

An exam paper contains the following equation for rocket propulsion: ) The error in the equation is that,instead of (v + ve) ,the velocity of the fuel relative to the ground should be

Stan argues that momentum cannot be conserved when a collision is not a head-on collision.Rachel insists it is conserved because each body receives an impulse of equal magnitude.Rachel is correct because

When the rate of burn and the exhaust velocity are constant,a rocket ascends with

An astronaut outside a spaceship hammers a loose rivet back in place.What happens to the astronaut as he swings the hammer?

A ball of mass mB is released from rest and acquires velocity of magnitude vB before hitting the ground.The ratio of the impulse delivered to the Earth to the impulse delivered to the ball is

The value of the momentum of a system is the same at a later time as at an earlier time if there are no

The law of conservation of momentum applies to a collision between two bodies since

A ball of mass mB is released from rest and acquires velocity of magnitude vB before hitting the ground.The ratio of the magnitude of the momentum the Earth acquires to the magnitude of the momentum the ball acquires is

In an elastic collision between two bodies of equal mass,with body 2 initially at rest,body 1 moves off at angle θ relative to the direction of its initial velocity and body 2 at angle φ.The sine of the sum of θ and φ,sin(θ + φ) ,is equal to

A steel ball bearing of mass m1 and speed of magnitude v1 has a head-on elastic collision with a steel ball bearing of mass m2 at rest.Rank the speed v1 of m1 relative to v2,the magnitude of the speed of m2,after the collision when i.m1 > m2;ii) m1 = m2;and iii) m1 < m2.

A ball of mass m_B is released from rest and acquires velocity of magnitude v_B before hitting the ground.The ratio of the kinetic energy the Earth acquires to the kinetic energy the ball acquires is

An exam paper contains the following equation for rocket propulsion: ) The error in the equation is that,instead of (v + v_e) ,the velocity of the fuel relative to the ground should be

A ball of mass m_B is released from rest and acquires velocity of magnitude v_B before hitting the ground.The ratio of the impulse delivered to the Earth to the impulse delivered to the ball is

A ball of mass m_B is released from rest and acquires velocity of magnitude v_B before hitting the ground.The ratio of the magnitude of the momentum the Earth acquires to the magnitude of the momentum the ball acquires is

A steel ball bearing of mass m₁ and speed of magnitude v₁ has a head-on elastic collision with a steel ball bearing of mass m₂ at rest.Rank the speed v₁ of m₁ relative to v₂,the magnitude of the speed of m₂,after the collision when i.m₁ > m₂;ii) m₁ = m₂;and iii) m₁ < m₂.