Exam 8: Momentum,impulse,and Collisions

A 1.0-kg block and a 2.0-kg block are pressed together on a horizontal frictionless surface with a compressed very light spring between them.They are not attached to the spring.After they are released and have both moved free of the spring

In the figure,determine the character of the collision.The masses of the blocks,and the velocities before and after are given,and no other unbalanced forces act on these blocks.The collision is

A 1000-kg car approaches an intersection traveling north at 20.0 m/s.A 1200-kg car approaches the same intersection traveling east at 22.0 m/s.The two cars collide at the intersection and lock together.Ignoring any external forces that act on the cars during the collision,what is the velocity of the cars immediately after the collision?

A car heading north collides at an intersection with a truck of the same mass as the car heading east.If they lock together and travel at 28 m/s at 46° north of east just after the collision,how fast was the car initially traveling? Assume that any other unbalanced forces are negligible.

On a smooth horizontal floor,an object slides into a spring which is attached to another mass that is initially stationary.When the spring is most compressed,both objects are moving at the same speed.Ignoring friction,what is conserved during this interaction?

In a perfectly ELASTIC collision between two perfectly rigid objects

In the figure,determine the character of the collision.The masses of the blocks,and the velocities before and after are given.The collision is

In an INELASTIC collision between two objects

Jacques and George meet in the middle of a lake while paddling in their canoes.They come to a complete stop and talk for a while.When they are ready to leave,Jacques pushes George's canoe with a force to separate the two canoes.What is correct to say about the final momentum and kinetic energy of the system if we can neglect any resistance due to the water?

A 15-g bullet is shot vertically into an 2-kg block.The block lifts upward 8.0 mm (see the figure).The bullet penetrates the block and comes to rest in it in a time interval of 0.0010 s.Assume the force on the bullet is constant during penetration and that air resistance is negligible.The initial kinetic energy of the bullet is closest to

A pool player is attempting a fancy shot.He hits the cue ball giving it a speed of 5.57 m/s and directs its center on a path tangent to the surface of the target ball having the same mass as the cue ball.After the collision (on a frictionless table)the initially-stationary ball moves with a speed of 4.82 m/s.After the collision,the new speed of the cue ball and the relative direction of the balls are closest to

A uniform piece of wire,20 cm long,is bent in a right angle in the center to give it an L-shape.How far from the bend is the center of mass of the bent wire?

A shell explodes into two fragments,one fragment 25 times heavier than the other.If any gas from the explosion has negligible mass,then

Two automobiles traveling at right angles to each other collide and stick together.Car A has a mass of 1200 kg and had a speed of 25 m/s before the collision.Car B has a mass of 1600 kg.The skid marks show that,immediately after the collision,the wreckage was moving in a direction making an angle of 40° with the original direction of car A.What was the speed of car B before the collision,assuming that any other unbalanced forces are negligible?

A 1.2-kg spring-activated toy bomb slides on a smooth surface along the x-axis with a speed of 0.50 m/s.At the origin 0,the bomb explodes into two fragments.Fragment 1 has a mass of 0.40 kg and a speed of 0.90 m/s along the negative y-axis.In the figure,the angle θ,made by the velocity vector of fragment 2 and the x-axis,is closest to

A 5.00-kg ball is hanging from a long but very light flexible wire when it is struck by a 1.50-kg stone traveling horizontally to the right at 12.0 m/s.The stone rebounds to the left with a speed of 8.50 m/s,and the ball swings to a maximum height h above its original level.The value of h is closest to

In the figure,a 60-cm length of uniform wire,of 60 g mass and negligible thickness,is bent into a right triangle.The x and y coordinates of the center of mass,in cm,are closest to

A long thin rod of length L has a linear density λ(x)= Ax where x is the distance from the left end of the rod. (a)How far is the center of mass of the rod from the left end of the rod? (b)What is the mass of the rod?

A 2.3-kg object traveling at 6.1 m/s collides head-on with a 3.5-kg object traveling in the opposite direction at 4.8 m/s.If the collision is perfectly elastic,what is the final speed of the ?

A 2.00-m rod of negligible mass connects two very small objects at its ends.The mass of one object is 1.00 kg and the mass of the other is unknown.The center of mass of this system is on the rod a distance 1.60 m from the 1.00-kg mass object.What is the mass of the other object?