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
