PSSI: Chapter 3 Quiz

A cannonball shot from a cannon with a long barrel will have a greater muzzle velocity because the cannonball receives a greater

Impulse

A feather and a coin dropped in a vacuum fall with equal

Accelerations

A car traveling along the highway needs a certain amount of force exerted on it to stop. More stopping force may be required when the car has - More mass - All of these - None of these - Less stopping distance - More momentum

All of these

A moving object has: - Momentum - Energy - Velocity - Speed - All of these

All of these

You're driving down the highway and a bug spatters into your windshield. Which undergoes the greater change in momentum?

Both the same

When a rifle is fired, it recoils so both the bullet and rifle are set in motion. The rifle and bullet ideally acquire equal

But opposite amounts of momentum

A cannon recoils from firing a cannonball. The speed of the cannon's recoil is small because the

Cannon has more mass than the ball

An open freight car rolls friction-free along a horizontal track in a pouring rain that falls vertically. As water accumulates in the car, its speed

Decreases

Compared with the force that brings a small car to a stop, the force required to bring a heavy truck traveling at the same speed to a stop

Depends on the time involved

In bungee jumping, the change in a jumper's kinetic energy equals the average force of the bungee cord multiplied by the stretching

Distance

A freight train rolls along a track with considerable momentum. If it rolls at the same speed but has twice as much mass, its momentum is

Doubled

An object at rest may have

Energy

A heavy truck and a small truck roll down a hill. Neglecting friction, at the bottom of the hill, the heavy truck will have greater

Momentum

A moving object on which no forces are acting will continue to move with constant

Momentum

If an object has kinetic energy, then it also must have

Momentum

An object that has kinetic energy must be

Moving

No work is done by gravity on a bowling ball that rolls along a bowling alley because

The force on the ball is at right angles to the ball's motion

Suppose a gun were made of a strong but very light material. Suppose also that the pellet is more massive than the gun itself. For such a weapon

The target would be safer than the shooter

The difference between impulse and impact force involves the

Time the force acts

Two identical arrows, one with twice the kinetic energy of the other, are fired into a hay bale. The faster arrow will penetrate

Twice as far as the slower arrow

An object is raised above the ground gaining a certain amount of potential energy. If the same object is raised twice as high, it gains

Twice as much potential energy

If you push an object twice as far while applying the same force, you do

Twice as much work

One end of a long uniform log is raised to shoulder level. Another identical log is raised at its center to the same level. Raising the second log requires about

Twice as much work

If you do work on an object in half the time, your power output is

Twice the usual power output

The force that accelerates a rocket in outer space is exerted on the rocket by the

Exhaust gases

A car that travels twice as fast as another when braking to a stop will skid

Four times as far

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

Momentum is transferred to the ground when an apple falls on it. The momentum absorbed by the ground is

Greater than that of the apple only if the apple bounces

The force on an apple hitting the ground depends upon - The time of impact with the ground - All of these - The speed of the apple just before it hits - Whether or not the apple bounces

All of these

Strictly speaking, if any electrical device in your car is turned on (such as an air conditioner, headlights, or even a radio), more gasoline is burned by the engine. This statement is

Always true

A heavy pile drive starting from rest falls on a pile with a force that depends on the - All of these - Original potential energy of the driver - Original height of the driver - Distance the pile falls - None of these

All of these

Compared with falling on a wooden floor, a wine glass may not break when it falls to a carpeted floor because of the

Longer time to stop

Recoil is noticeable if we throw a heavy ball while standing on roller skates. If instead we go through the motions of throwing the ball but hold onto it, our net recoil will be

Zero

A bullet is fired from a gun. The speed of the bullet will be about the same as the speed of the recoiling gun

If the mass of the bullet equals the mass of the gun

Padded dashboards in cars are safer in an accident than nonpadded ones because an occupant hitting the dash has

Increased time of impact and decreased impact force

Compared to a recoiling rifle, the bullet fired has a greater

Kinetic energy

An object that has potential energy may have this energy because of its

Location

When you are in the way of a fast-moving object and can't get out of its way, you will suffer a smaller force of impact if you decrease its momentum over a

Long time

If the speed of a moving object doubles, then what else doubles?

Momentum

The impulse-momentum relationship is a direct result of

Newton's second law