Physical Science Final Exam Part 1

A train reduces its velocity from 16.7 m/s to 5.56 m/s in a time of 8 seconds. Find the acceleration.

-1.39 m/s2

A body is accelerating at 10 m/s2 with a velocity of 2 m/s in 4 sec. Find the initial velocity of the body?

-38 m/s

When a falling object gains 10 m/s each second, its acceleration is

10 m/s2

A tow truck exerts a force of 3000 N on a car that accelerates at 2 m/s2. The mass of the car must be

1500 kg

A 10-kg block is pushed across a friction-free horizontal surface with a horizontal force of 20 N. The acceleration of the block is

2 m/s2

A brick of salt measuring 200 cubic centimeters weighs 433 grams What is its density?

2.165 g/cm3

A metal body of mass 216 g occupies a volume of 80 cm3, what is the density?

2.7 g/cm3

A car has a mass of 1000 kg and accelerates at 2 m/s2. What is the magnitude of the force exerted on the car?

2000 N

When a 10-kg block is simultaneously pushed toward the east with 20 N and toward the west with 15 N, the combination of these forces on the block is

5 N east

A person is attracted toward the center of Earth by a 500-N gravitational force. The force of attraction of Earth toward the person is

500 N

An African elephant can reach heights of over 13 feet and possess a mass of 6000 kg. Determine the weight of the elephant.

58800 N

The scientist to first introduce the concept of inertia was

Galileo

If the mass of an object does not change, a constant net force on the object produces constant

acceleration

When you stand at rest on a pair of bathroom scales, the readings on the scales will always

add to equal your weight

A heavy object and a light object in a vacuum are dropped at the same time from rest. The heavier object reaches the ground

at the same time as the lighter object

A player hits a ball with a bat. If one part of the interaction is the bat against the ball, the other part is the

ball against the bat

While a crate rests on a horizontal floor the friction force acting on the crate is

between zero and the weight of the crate

The amount of friction that occurs when two blocks slide against each other depends on

both the stickiness of their surface and how much they are pressed together

A ball tossed vertically upward reaches its highest point and then falls back to its starting point. During this up-and-down motion the acceleration of the ball is always

directed downward

When you toss a coin straight up, it moves upward, turns around, and drops. During this time the acceleration of the coin is

downward and constant

Inside the interior of a truck that moves at constant velocity is a package that drops from the midpoint of the ceiling. The package hits the floor

exactly below the midpoint of the ceiling

Science greatly advanced when Galileo favored

experiment

Two objects of the same size but unequal weights are dropped from a tall tower. Taking air resistance into consideration, the object to hit the ground first will be the

heavier object

When a crate slides down an incline at a constant velocity it is

in dynamic equilibrium

If an object's mass decreases while a constant force acts on it, the acceleration

increases

During each second of free fall, the speed of an object

increases by the same amount

The acceleration of a cart moving down an inclined plane (a ramp)

increases with time

When dishes remain on a table when you yank the tablecloth beneath them, you're demonstrating

inertia

If you are carrying a heavy bag of groceries and bang your hand against the wall, the concept that best explains why you are hurt is

intertia

When a ball increases in speed by the same amount each second, its acceleration

is constant

your weight

is the gravitational attraction between you and earth

Whenever the net force on an object is zero, its acceleration

is zero

Galileo said that if you rolled a ball along a level surface it would

keep rolling without slowing down if no friction acted upon it.

A ball is thrown vertically into the air. Because of air resistance, its time coming down compared to its time going up is

more

The equilibrium rule F=0 applies to

objects or system at rest and that are moving in a straight line

A rock is thrown vertically upward. At the top of its straight-line path the force acting on it is

only the force due to gravity

According to Galileo, inertia is a

property of all matter

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

pull of the ball's mass on Earth

A heavy rock and a light rock in free fall have the same acceleration. Both rocks have the same acceleration because

ratio of force to mass is the same

An object is pulled with two forces, 10 N northward and 15 N southward. The direction of the net force is to the

south

A sheet of paper can be pulled from beneath a box of cereal without toppling it if the paper is jerked quickly. This best demonstrates that

the box has inertia

When you push your desk to the right, friction on the desk acts toward

the left

Compared with the mass of a certain object on Earth, the mass of the same object on the Moon is

the same

A Mack truck and a Mini Cooper traveling at the same speed collide head-on. The collision force is greatest on the

the truck and the mini cooper are the same

Compared with a 1-kg block of solid iron, a 2-kg block of solid iron has twice as much

volume, mass, inertia

An object in mechanical equilibrium is an object

with no acceleration, at rest, and moving at a constant velocity

The force required to maintain an object at a constant velocity in free space is equal to

zero

The speed of a vertically-thrown ball at the top of its path is

zero

When a falling object has reached its terminal velocity, its acceleration is

zero