Physics Test 5-6

A car traveling at 100 km/h strikes an unfortunate bug and splatters it. The force of impact is

A car traveling at 100 km/h strikes an unfortunate bug and splatters it. The force of impact is

The same for both.

(Action and Reaction on Different Masses)

When a tennis racquet hits a ball,

the ball hits the racquet.
(Action and Reaction on Different Masses)

When a cannonball is fired from a cannon, which undergoes the greater acceleration?

the cannonball
(Action and Reaction on Different Masses)

A pair of toy freight cars, one twice the mass of the other, fly apart when a compressed spring that joins them is released. The spring exerts the greater force on the

same on each.
(Action and Reaction on Different Masses)

A pair of toy freight cars, one twice the mass of the other, fly apart when a compressed spring that joins them is released. Acceleration will be greater for the

lighter car.
(Action and Reaction on Different Masses)

The force that propels a cannonball when fired from a cannon is

equal and opposite to the force the ball exerts on the cannon.

Joshua is attracted toward Earth by a 500-N gravitational force. The Earth is attracted toward Joshua with a force of

500 N.
(Action and Reaction on Different Masses)

As a ball falls, the action force is the Earth's pull on the ball. The reaction force is the

ball's pull on Earth.
(Action and Reaction on Different Masses)

A pair of air pucks on an air table are set in motion when a compressed spring between them is released. If one puck moves with twice the speed of the other, then its mass is

half the mass of the other.
(Action and Reaction on Different Masses)

You cannot exert a force on a wall

unless the wall simultaneously exerts the same amount of force on you.
(Forces and Interactions)

To say there is no such thing as only one force means

there must also be a corresponding reaction force.
(Forces and Interactions)

When you drop a rubber ball on the floor it bounces back. The force exerted on the ball to produce bouncing is by the

floor.
(Forces and Interactions)

When a boxer hits a punching bag, the strength of his punch depends on how much force the bag can

exert on the boxer's fist.
(Forces and Interactions)

Your friend says that the heavyweight champion of the world cannot exert a force of 50 N on an isolated piece of tissue paper with his best punch. You

agree that it can't be done.
(Forces and Interactions)

When a skateboarder pushes on a wall,

all the above.
(Forces and Interactions)

A piece of rope is pulled by two people in a tug-of-war. Each exerts a 400-N force. What is the tension in the rope?

400 N
(Forces and Interactions)

The winner in a tug-of-war exerts the greatest force on

the ground.
(Forces and Interactions)

A pair of action-reaction forces always

occur simultaneously.
(Vectors and the Third Law)

When you walk, you push on the floor to the left and the floor

pushes you to the right.
(Vectors and the Third Law)

Harry pulls on the end of a spring attached to a wall. The reaction to Harry's pull on the spring is

the spring pulling on Harry.
(Vectors and the Third Law)

Action and reaction pairs of forces

always act simultaneously.
(Vectors and the Third Law)

For every action force, there must be a reaction force that

is equal in magnitude.
(Vectors and the Third Law)

An archer shoots an arrow. Consider the action force to be the bowstring against the arrow. The reaction to this force is the

arrow's push against the bowstring.
(Vectors and the Third Law)

When a karate chop breaks a board with a 3000-N blow, the amount of force that acts on the hand is

3000 N
(Vectors and the Third Law)

To produce an acceleration to a system there

must be a net force on the system.
(Vectors and the Third Law)

A player hits a ball with a bat. If action is the force of the bat against the ball, reaction is the

force that the ball exerts on the bat.

(Vectors and the Third Law)

A player catches a ball. If action is the force of the ball against the player's glove, reaction is the

glove against the ball.
(Vectors and the Third Law)

Neglecting air resistance, once a tossed ball leaves your hand

only the force due to gravity acts on it.
(Vectors and the Third Law)

An automobile and a golf cart traveling at the same speed collide head-on. The impact force is

the same for both.
(Vectors and the Third Law)

A Mack truck and a Volkswagen traveling at the same speed have a head-on collision. The vehicle that undergoes the greatest change in velocity will be the

Volkswagen.
(Vectors and the Third Law)

Nellie Newton pulls her sled by a rope that is 45° to the horizontal. The horizontal and vertical components of force are

both of these.
(Vectors and the Third Law)

Nellie's weight and normal force usually have the same magnitude when she stands on a

horizontal surface.
(Vectors and the Third Law)

When Nellie hangs suspended from a pair of ropes that are not vertical, the tension in each rope is

more than half her weight.
(Vectors and the Third Law)

As the sloped surface supporting a shoe becomes steeper

all of these.
(Vectors and the Third Law)

A vertical vector of 3 units combined with a horizontal vector of 4 units has a resultant of

5 units.
(Vectors and the Third Law)

If vertically falling rain makes slanted 45° streaks on the side windows of a moving car, the speed of the car

equals the speed of the falling drops.
(Vectors and the Third Law)

Nellie tosses a ball upward at an angle. Neglecting air resistance, the horizontal component of the initial velocity

remains constant.
(Vectors and the Third Law)

Nellie tosses a ball upward at an angle. Neglecting air resistance, the vertical component of the initial velocity

decreases with time to reach the top.
(Vectors and the Third Law)

The airspeed of an airplane is 200 km/h. When it is caught in a 200-km/h crosswind, its speed across the ground below is

283 km/h.
(Vectors and the Third Law)

A river 100 m wide flows due south. A boat that goes 1 m/s relative to the water is pointed due east as it crosses from the west bank. The boat crosses in

100 s.
(Vectors and the Third Law)

The greater efficiency achieved with the curved blades of a Pelton wheel is due to

bouncing
(Bouncing)

A karate chop is more effective if one's hand

bounces upon impact.
(Bouncing)

A softer landing occurs when an falling object bounces from a surface

in a extended time.
(Bouncing)

A piece of putty moving with 1 unit of momentum strikes and sticks to a heavy bowling ball that is initially at rest. Both move with a combined momentum of

1 unit.
(Collisions)

Two identical gliders slide toward each other on an air track. One moves at 1 m/s and the other at 2 m/s. They collide, stick, and moves at

1/2 m/s.
(Collisions)

A red car has a head-on collision with an approaching blue car with the same magnitude of momentum. A green car driving with the same momentum as the other cars collides with an enormously massive wall. Which of the three cars will experience the greatest impulse?

all the same.
(Collisions)

Two identical freight cars roll without friction (one at 1 m/s, the other at 2 m/s) toward each other on a level track. They collide, couple together, and roll away in the direction of

the faster car.
(Collisions)

Two 5000-kg rail cars roll without friction (one at 1 m/s, the other at 2 m/s) toward each other on a level track. They collide, couple, and roll together with a combined momentum of

5000 kg m/s.
(Collisions)

The conservation of momentum is most closely related to

Newton's 3rd law.
(Conservation of Momentum)

When bullets are fired from an airplane in the forward direction, the momentum of the airplane is

decreased.
(Conservation of Momentum)

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

both the same
(Conservation of Momentum)

An astronaut floating alone in outer space throws a baseball. If the ball moves away at 20 m/s, the astronaut will

move in the opposite direction at a lower speed.
(Conservation of Momentum)

A fan attached to an ice sailcraft stalled on a windless day blows air into the sail that bounces backward upon impact. The boat

moves in the direction of the wind impact force.
(Conservation of Momentum)

If all people, animals, trains and trucks all over the world began to walk or run towards the east (opposite the direction of Earth's spin), then

Earth would spin a bit slower.
(Conservation of Momentum)

Padded dashboards in cars are safer in an accident than non-padded ones because passengers hitting the dashboard encounter

lengthened time of contact.
(Impulse)

When Peter tosses an egg against a sagging sheet, the egg doesn't break due to

neither of these
(Impulse)

Compared with 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.
(Impulse Changes Momentum)

It is correct to say that impulse is equal to

a corresponding change in momentum.
(Impulse Changes Momentum)

The impulse-momentum relationship is a direct result of

Newton's 2nd law
(Impulse Changes Momentum)

Which produces more force: driving into a very massive concrete wall with no "give," or having a head-on collision with an identical car moving toward you at the same speed?

both the same
(Impulse Changes Momentum)

If you can't avoid being hit by a fast-moving object, you'll suffer a smaller contact force if you can extend that force over a

longer time.
(Impulse Changes Momentum)

Whether a truck comes to a stop by crashing into a haystack or a brick wall, the stopping force is

greater with the brick wall.
(Impulse Changes Momentum)

Whether a truck comes to a stop by crashing into a haystack or a brick wall, the impulse is

both the same.
(Impulse Changes Momentum)

When a boxer moves into an oncoming punch, the force experienced is

increased.
(Impulse Changes Momentum)

When a boxer is moving away from a punch, the force experienced is reduced because

the time of contact is increased.
(Impulse Changes Momentum)

A karate expert executes a swift blow and breaks a cement block with her bare hand. The magnitude of the force on her hand is

the same as the force applied to the block.
(Impulse Changes Momentum)

A tiny gun made of a strong but very light material fires a bullet more massive than the gun itself. For such a weapon

the target would be safer than the shooter.
(Impulse Changes Momentum)

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

cannon has much more mass than the cannonball.
(Impulse Changes Momentum)

The average braking force of a 1000-kg car moving at 10 m/s braking to a stop in 5 s is

2000 N.
(Impulse Changes Momentum)

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

exhaust gases.
(Impulse Changes Momentum)

A same-size iron ball and wooden ball are dropped simultaneously from a tower and reach the ground at the same time. The iron ball has a greater

momentum.
(Momentum)

The speed of a 4-kg ball with a momentum of 12 kg m/s is

3 m/s.
(Momentum)

Which has the greater momentum when moving?

either of these depending on speed.
(Momentum)

Which of the following has the largest momentum relative to Earth's surface?

a pickup truck speeding along a highway (Momentum)

If several balls are thrown straight up with different initial speeds, the quantity that will have the same value along their paths is their

acceleration.
(Momentum)

A cannonball following a parabolic path explodes into fragments. The momentum of the fragments

continue along the path as if the explosion didn't occur.
(More Complicated Collisions)

Two vehicles with equal magnitudes of momentum traveling at right angles to each other undergo an inelastic collision. The magnitude of momentum for the combined wreck is

greater than the magnitude of momentum of either car before collision.
(More Complicated Collisions)

When a vertically falling firecracker bursts, the vector sum of momentum fragments

both of these.
(More Complicated Collisions)

Two vehicles with equal magnitudes of momentum traveling at right angles to each other undergo an inelastic collision. The combined wreck moves in a direction

at 45 degrees to the direction of either car before collision.
(More Complicated Collisions)

A 5000-kg freight car moving at 2 m/s collides with a 10,000-kg freight car at rest. They couple upon collision and move away at

2 m/s.
(Collisions)