Exam 9: Linear Momentum and Collisions

A 6.0-kg object,initially at rest in free space,"explodes" into three segments of equal mass.Two of these segments are observed to be moving with equal speeds of 20 m/s with an angle of 60° between their directions of motion.How much kinetic energy is released in this explosion?

Three particles are placed in the xy plane.A 30-g particle is located at (3,4)m,and a 40-g particle is located at (−2,−2)m.Where must a 20-g particle be placed so that the center of mass of the three-particle system is at the origin?

A car of mass m₁ traveling at velocity v passes a car of mass m₂ parked at the side of the road.The momentum of the system of two cars is

A 10-g bullet moving 1000 m/s strikes and passes through a 2.0-kg block initially at rest,as shown.The bullet emerges from the block with a speed of 400 m/s.To what maximum height will the block rise above its initial position? ​ ​

A 3.0-kg object moving in the positive x direction has a one-dimensional elastic collision with a 5.0-kg object initially at rest.After the collision the 5.0-kg object has a velocity of 6.0 m/s in the positive x direction.What was the initial speed of the 3.0 kg object?

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: M₁v_1i 0 = m₁v_1f cosθ + m₂v_2f sinφ = m₁v_1f sinθ + m₂v_2f cosφ What error(s)has the student made?

A 3.0-kg mass is sliding on a horizontal frictionless surface with a speed of 3.0 m/s when it collides with a 1.0-kg mass initially at rest as shown in the figure.The masses stick together and slide up a frictionless circular track of radius 0.40 m.To what maximum height,h,above the horizontal surface will the masses slide?

A 3.00-kg stone is dropped from a 39.2 m high building.When the stone has fallen 19.6 m,the magnitude of the impulse the Earth has received from the gravitational force exerted by the stone is

A 500-g firework explodes into two pieces of equal mass at an instant when it is traveling straight up at 10 m/s.If one half shoots off horizontally to the left at 20 m/s,what is the velocity,in m/s,of the other half immediately after the explosion? (The x axis is directed right;the y axis up. )

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

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

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 0.28-kg stone you throw rises 34.3 m in the air.The impulse your hand receives from the stone while it throws the stone is

The linear density of a rod,in g/m,is given by )The rod extends from the origin to x = 0.400 m.What is the mass of the rod?

A 1.6-kg block is attached to the end of a 2.0-m string to form a pendulum.The pendulum is released from rest when the string is horizontal.At the lowest point of its swing when it is moving horizontally,the block is hit by a 10-g bullet moving horizontally in the opposite direction.The bullet remains in the block and causes the block to come to rest at the low point of its swing.What was the magnitude of the bullet's velocity just before hitting the block?

An 80-g particle moving with an initial speed of 50 m/s in the positive x direction strikes and sticks to a 60-g particle moving 50 m/s in the positive y direction.How much kinetic energy is lost in this collision?

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 3.0-kg mass sliding on a frictionless surface explodes into three 1.0-kg masses.After the explosion the velocities of the three masses are: (1)9.0 m/s,north; (2)4.0 m/s,30° south of west;and (3)4.0 m/s,30° south of east.What was the magnitude of the original velocity of the 3.0-kg mass?

A 0.28-kg stone you throw rises 34.3 m in the air.The impulse the stone receives from your hand while being thrown is

The speed of a 2.0-kg object changes from 30 m/s to 40 m/s during a 5.0-s time interval.During this same time interval,the velocity of the object changes its direction by 90°.What is the magnitude of the average total force acting on the object during this time interval?