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