Chapter 5,6,7
Two billiards balls having the same mass and speed roll toward each other. What is their combined momentum after they meet?
0
A piece of Putty moving with 1 unit of momentum strikes and stick to a heavy bowling ball that is initially at rest. After the putty sticks to the ball, both move with a combined momentum of
1 unit
A bungee jumper attains a speed of 30 m/s just as the bungee cord begins to stretch. If the period of stretch is 2 s, the magnitude of the jumpers average deceleration is about
1.5 g
A 5kg shark swimming at a speed of 1 m/s swallows an absent-minded 1 kg fish swimming toward it at 4 m/s. the speed of the shark after this meal is
1/6 m/s
Consider massive gliders that slide friction free along a horizontal air track. Glider A has a mass of 1 kg, a speed of 1 m/s, and collides with glider B that has a mass of 5 kg and is at rest. If they stick upon collision, their speed after collision will be
1/6 m/s
Consider a hydraulic press. When the input piston is depressed 20 cm, the output piston is raised 1 cm. On the same press, an input force if 1 N can lift a load of
10 N
Neglecting air resistance, a man on a high ladder releases a ball which strikes the ground with 100 J of Kinetic energy. If he were to throw it straight upward instead, it will eventually reach the ground with a Kinetic energy of
100 J
A car moves 4 times as fast as another identical car. compared to the slower car, the faster car has
16 times the KE
A 5000kg freight car moving at 2 m/s runs into a 10,000kg freight car at rest. They couple upon collision and move away as one body at
2 m/s
A 1000 kg car moving at 10 m/s brakes to a stop in 5 s. The average braking force is
2000 N
A 2500 N pile driver ram falls 10m and drives a post 0.1m into the ground. The average impact force on the ram is
250,000 N
A karate chop delivers a blow of 3000 N to a board that breaks. The force that acts on the hand during this event is
3000 N
Two people, one twice as massive as the other, attempt a tug of war with 12 m of massless rope on a frictionless ice. After a brief time, they meet. The heavier person slides a distance of
4 m
A piece of rope is pulled by two people in a tug of war. Each pulls with 400 N of force. what is the tension in the rope?
400 N
Using 1000 J of work a toy elevator is raised from the ground floor to the second floor and 20 seconds, the power needed to do this job was
50 W
The change in momentum, in kg m/s that occurs when a 1.0kg ball traveling at 4.0 m/s strikes a wall and bounces back at 2.0 m/s is
6
A 5000kg freight car runs into a 10,000kg freight car at rest. They couple upon collision and move with a speed of 2 m/s. What was the initial speed of the 5000kg car?
6 m/s
A vehicle that weighs 400N on the surface of the earth is traveling in outerspace at a speed of 400 m/s. It can be stopped by applying a constant force of 20 N for?
800 seconds
Which of the following has the largest momentum relative to the earth surface
A pick up truck speeding along the highway
A moving object has
ALL OF THESE velocity Energy Momentum Speed
A hydraulic press, like an inclined plane, is capable of increasing energy
ALWAYS FALSE
When you jump from an elevated position you usually bend your knees upon reaching the ground. by doing this, you make the time of the impact about 10 times as great as for a stiff Legged landing. In this way the average force your body experiences is
About 1/10 as great
Your friend says that the heavyweight champion of the world cannot exert force of 50 N on a piece of tissue paper with his best punch. The tissue paper is held in mid air - no wall, no tricks. you?
Agree that it CANT BE DONE
An archer shoots an arrow. Consider the action force to be the bowstring against the arrow. The reaction to this force is the?
Arrows push against the bowstring
Which would produce more force: driving into a very massive concrete wall with no "give" or having a head on collision at the same speed with an identical car moving toward you with the same speed?
Both the same
A player catches a ball. Consider the action force to be the impact of the ball against the players glove. The reaction to this force is the
Force the glove exerts on the ball
A heavy truck and a small car rolling down a hill at the same speed are forced to stop in the same amount of time. compared to the force that stops the car, The force needed to stop the truck is
Greater
For an action force, there must be a reaction force that
Is exactly equal in magnitude
A ball is projected into the air with 100 J of Kinetic energy which is transformed into a gravitational potential energy at the top of its trajectory. when it returns to its original level after encountering air resistance, it's kinetic energy is
Less than 100 J
If an object has kinetic energy, then it also must have
Momentum
A large metal ball is shot from a cannon with a short barrel. If the same ball were to be shot from cannon with a longer barrel, it's muzzle velocity would be
More
A golf ball moving forward with 1 unit of momentum strikes and bounces backwards off a heavy bowling ball that is initially at rest and free to move. The bowling ball is set in motion with a momentum of
More than 1 unit
A 1kg ball dropped from a height of 2m rebounds only 1.5m after hitting the ground. The amount of energy converted to heat is about
More than 2.0 J
If a monkey floating in outer space throws his hat away, the hat and the monkey will both
Move away from each other, but at different speeds.
An astronaut, floating alone in outer space, throws a baseball if the ball float away at a speed of 20 meters per second, the astronaut will
Move in the opposite direction, but at lower speed
A light aluminum ball and a heavy lead ball if the same size are allowed to roll down an incline. When they are halfway down the incline, they will have identical
NONE OF THE CHOICES ABOVE
A large heavy truck and a small baby carriage roll down a hill. Neglecting friction, at the bottom of the hill, the baby carriage will have greater
NONE OF THESE. Speed Momentum Acceleration
The impulse momentum relationship is a direct result of
Newton's 2nd law
If you push for a half hour or a whole hour against a stationary wall
No work on the wall is done for in either case
A woman carries a heavy box across a Rome at a constant speed how much work does she do or the box while walking?
None
A sandbag is motionless in outer-space. A second sandbag with 3 times the mass moving at 12 m/s collides with it. they stick together and move at a speed of
None of these
As a ball falls, the action force is the pull of earth on the ball. The reaction force is the?
Pull of the balls mass on the earth
Compared to falling on a stone floor, a wine glass may not break when it falls on a carpeted floor because the
Stopping time is longer on the carpet
A flower pot mass m falls from rest to the ground below, a distance h. Which statement is correct?
The KE of the pot when it hits the ground is proportional to h
It is correct to say that impulse is equal to
The change in momentum that it produces
After rolling halfway down an incline a marble's kinetic energy is
The same as its potential energy
A car traveling at 100 km/hr strikes an unfortunate bug and splatters it. the force of impact is?
The same for both
If you do work on an object in one third the usual time, your power output is
Three times the usual power output
To catch a ball, a baseball player extends the hand forward before impact with the ball and then let it ride backward in the direction of the balls motion. doing this reduces the force of impact on the players hand principally because the
Time of impact is increased
If you push and object twice as far while applying the same force, you do
Twice as much work
