35 terms

# Chapter 7 Conceptual Physics Test

Miss kelce Newton's third law of motion

#### Terms in this set (...)

a force is exerted on the tires of a car to accelerate the car along the road. The force is exerted by the
If a horse pulls on a wagon at rest, the wagon pull back equally on the horse. Can the wagon be set into motion?
Yes, because there is a net force acting on the wagon.
As a ball falls, the action force is the pull of Earth's mass on the ball. What is the reaction to this force?
The pull of the ball's mass on Earth
A rocket is able to accelerate in the vacuum of space when it fires its engine. The force that propels the rocket is the force
of the exhaust gases on the rocket
you drive past a farm, and you see a cow pilling a plow to till a field. You have just learned about Newton's third law, and you wonder how the cow is able to move forward if the plow is exerting an equal and opposite force on the cow. Which of the following explains the movement of the cow and plow?
The force exerted by the cow on the plow is smaller than the force that the cow exerts on the ground to move forward.
A karate chop delivers a blow of 2300N to a board that breaks. The Force that acts on the hand during this feat
is 2300N
According to Newton's third law, if you push gently on something, it will push
gently on you
Whenever an object exerts a force on another object, the second object exerts a force of the same magnitude, but in the opposite direction to that of the first object.
always true
A woman weighing 550 N sits on the floor. She exerts a force on the floor of
550 N
Bronco the skydiver falls toward Earth. The attraction of Earth on Bronco pulls him down. The reaction to this force is
Bronco pulling up on Earth
Forces always occur
in pairs
An unfortunate bug splatters against the windshield of a moving car. Compared to the force of the car on the bug, the force of the bug on the car is
the same
An unfortunate bug splatters against the windshield of a moving car. Compared to the decoration of the car, the declaration of the bug is
larger
A player catches a ball. Consider the action force to be the impact of the ball against the player's glove. What is the reaction to this force
The force the glove exerts on the ball
A player hits a ball with a bat. The action force is the impact of the bat against the ball. What is the reaction to this force?
The force of the ball against the bat
Suppose you accidentally drive into a tree. Which of the following correctly describes the interaction between your car and the tree?
The car and the tree mutually exert equal and opposite forces on each other
A high school student hits a nail with a hammer. During the collision, there is a force
on the nail and also on the hammer
If your car runs out of gas, why can't you push on the car's windshield from the inside to move it?
In order for the car to move, a force must be exerted by the car on the ground.
Suppose two people, one having three times the mass of the other, pull on opposite sides of a 20-meter rope while on friction-less ice. After a brief time, they meet. The more massive person slides a distance of?
5m
A person is attracted towards the center of Earth by a 470N gravitational force. The force with which Earth is attracted toward the person is
470N
A large truck and a small car traveling at the same speed have a head-on collision. The vehicle to undergo the greater change in velocity will be
A small car
Nellie Newton holds an apple in her hand. If action is the earth pulling on the apple, then reaction is:
Neither A nor B
If you exert a force of 12,000 N on a 3,000 kg car and a 6,000 kg truck that are both originally at rest, what will be the resulting accelerations of the objects?
The car will accelerate 4 m/s2 and the truck will accelerate 2 m/s2
The Earth pulls on the moon. Similarly the moon pulls on the Earth, evidence that the
Both of these
As a 600-N woman sits on the floor, the floor exerts a force on her of
600 N
a bicycle and a parked car have a head -on collision. the force of impact is greater on the bicycle.
false
in order to make a cart move forward, a horse mist pill harder on the cart pulls on the horse
false
whenever one object exerts a force on another object, the second object always exerts a force back on the first object.
true
a rocket ship is pushed forward by gases that are forced out the back of the ship
true
if a train is pilling a caboose, the caboose will move of the train exerts a force on the ground that is greater than the force that the caboose exerts on the train.
true
Explain how Newtons third law applies to a cannon launching a cannonball? Which has the larger acceleration, the cannonball or the cannon ? What if the cannonball were just as massive as the cannon-how fast would the cannon move compared to the cannonball ?
A cannon has more mass and therefore would have less acceleration under Newton's third law. The cannonball has less mass and would have more acceleration. If both has the same masses, then both would accelerate at the same speed.
A pair of blocks, one 2 times as massive as the other, are connected by a compressed spring. When the spring is released, the blocks fly apart. Compared to the heavier block, how many times as fast does the lighter block accelerate?
The lighter block accelerates 2 times faster because it has 2 times less mass than the other block.
A fighter punches a sheet of paper in midair, and brings it from rest up to a speed of 40 m/s in 0.08 s. What is the force of impact on the paper if the mass of the paper is 0.01 kg?
a=v/t a=40/0.08=500 F=ma F=500 x 0.01 F=5 N
If you push off the ground with a force of 350 N when you jump upward, what force pushes Earth downward?
Your force pushes the Earth downward by 350 N
A 60-kg person on in-line skates pushes against a wall with a force of 30 N and recoils. What acceleration does that person experience?
a=F/m a=30/60 a=0.5m/s^2