127 terms

A testable prediction is a(n)

hypothesis

When designing an experiment, the first step is to

state the problem

A standard for comparison that helps to ensure that the experimental result is caused by the condition being tested is the

control

A factor that changes in an experiment from manipulation of the independent variable is the

dependent variable

A factor that does not change in an experiment is the

constant

An organized process used to gather observations and test a hypothesis is a(n)

experiment

A statement that describes what happens in nature is a

scientific law

An explanation of an event that is based on repeated observations and experiments is a

theory

An idea, event, or object that can be used to represent something you are trying to explain is a

model

The lightbulb is an example of

technology

In an experiment to determine if the popping or popcorn is affected by the temperature at which it is stored, counting the popped kernels is an example or a(n)

observation

A measurement standard is defined as

an exact quantity people agree to use for comparison

The correct symbol for the SI unit of temperature is

K

In a graph, the variable on the horizontal axis is the

independent variable

The type of graph that would be used to show how some fixed quantity is broken down into parts is a

circle graph

In a graph showing how the temperature of a material changes over time, temperature change is the

dependent variable

A unit of measurement that is obtained by combining other units is a __ unit

derived

Of the following, the most correct way to express density is

g/cm^3

Of the following, the only unit that cannot be used to express volume is

kg

If you ride your bike down a straight road for 500m then turn around and ride back, your distance is __ your displacement.

greater than

Motion is a change in

position

The speed you read on a speedometer is

instantaneous speed

3m/s north is an example of a(n)

velocity

The relationship among speed, distance, and time is

s= d/t

A single point on a distance-time graph tells that

instantaneous speed

A merry-go-round horse moves at a constant speed but at a changing

velocity

Acceleration is rate of change of

velocity

If you ride your bike up a hill, then ride down the other side, your acceleration is

first negative, then positive

The equation used to find acceleration is a

vf-vi/t

Inertia varies depending on

force

Newton's first law of motion is also called law of

inertia

Examine figure 11-1. If you were standing under the tree, which object would appear to be moving?

the airplane

a passenger in the rear seat of a car moving at a steady speed is at rest relative to

the front seat of the car

Which distance can be most accurately measured with a ruler?

the width of a book

On kilometer equals 1000 meters. What does the prefix kilo- means?

1000

What is the most appropriate SI unit to express the speed of a cyclist in the last leg of a 10-km race?

km/h

Speed is the ratio of the distance an object moves to

the amount of time needed to travel the distance

Instantaneous speed is measured

at a particular instant

A horizontal line on a distance-time graph means the object is

at rest

The rate at which velocity changes is called

acceleration

Which example describes constant acceleration due ONLY to a change in direction?

traveling around a circular track

An object that is accelerating may be

all of the above (slowing down, gaining speed, changing direction)

What is instantaneous acceleration?

how fast a velocity is changing at a specific instant

Which of the following statements is true?

An object at rest has an instantaneous acceleration of zero.

The upward force on an object falling through the air is

air resistance

The relationship among mass, force , and acceleration is explained by

Newton's second law of motion

A feather will fall through the air more slowly than a brick because of

Air resistance

In the absence of air, a penny and a feather that are dropped from the same height at the same time will

fall at the same reate

The acceleration due to gravity is

9.8 m/s^2

According to Newton's second law of motion

F=ma

When an object moves in a circular path, it accelerates toward the center of the circle as a result of

centripetal force

The path of a projectile is

curved

For any object, the greater the force that's applied to it, the greater its ___ will be.

acceleration

The size of the gravitational force between two objects depends on their

masses and the distance between them

When a force is exerted on a box, an equal and opposite force is exerted by the box. These forces are called __ forces.

action-reaction

A real care moving at 10 km/h has more momentum than a toy car moving at the same speed because the real car

has greater mass

In the equation p=mv, the p represents

momentum

The statement "to every action there is an equal and opposite reaction" is

Newton's third law of motion

The unit of momentum is

kgxm/s

When two balls collide, the momentum of the balls after the collision is explained by

the law of conservation of momentum

An object that is in free fall seems to be

weightless

If gravity did NOT affect the path of a horizontally thrown ball, the ball would

fall straight

The SI unit of force is the

newton

Which of the following relationships is correct?

1N = 1 kgm/s^2

When an unbalanced force acts on an object

the object accelerates

When a pair of balanced forces acts on an object, the net force that results is

equal to zero

What kind of frictions occurs as a fish swims through water?

fluid

As you push a cereal box across a tabletop, the sliding friction acting on the cereal box

acts in the direction opposite of motion

The forces acting on a falling leaf are

gravity and air resistance

An open parachute increases air resistance of a falling sky diver by

increasing surface area

Projectile motion is caused by

the downward force of gravity and an initial forward velocity.

The property of matter that resists changes in motion is called

inertia

An orange might roll off your cafeteria tray when you stop suddenly because of

the orange's inertia

According to Newton's second law of motion, the acceleration of an object equals the net force actin on the object divided by the object's

mass

Your weight equals your

mass times the acceleration due to gravity

The acceleration due to gravity on the surface of Mars is about one third the acceleration due to gravity on Earth's surface. The weight of a space probe on the surface of Mars is about

one third its weight on Earth's surface.

Newton's third law of motion describes

action and reaction forces

In which of the following are action and reaction forces involved?

all of the above

The product of an object's moss and velocity is its

momentum

What force is responsible for the repulsion between two positively-charged particles

electric

When opposite poles of two magnets are brought together, the poles

attract each other

Which universal force acts only on the protons and neutrons in a nucleus

strong nuclear

With which of the following is the weak nuclear force associated?

nuclear decay

Which of the following universal forces is the weakest?

gravitational

As an astronaut travels far away from Earth, her weight

decreases because gravity decreases

The gravitational force between two objects increases as mass

increases or distance decreases.

The force that keeps an object in a circle is called

centripetal force

Which of the following is not used to calculate kinetic energy?

height

Which of the following is not used to calculate potential energy?

speed

Thermal energy is measured in

joules

The __ energy of an object increases with its height.

potential

The kinetic energy of an object increases as its __ increases.

speed

Mechanical energy is the total kinetic and __ energies in a system.

potential

__ can cause kinetic energy to change into thermal energy.

friction

Green plants convert light energy from the sun into

chemical potential energy

The mechanical energy of a coconut falling from a tree

remains constant

The law of __ states that energy in a system can change forms but can never be created or destroyed.

conservation of energy

The kinetic energy of an object increases as its __ increases

velocity

Increasing the speed of an object __ its potential energy.

does not affect

The SI unit for energy is the

joule

You can calculate kinetic energy by using the equation

KE=1/2m x v^2

You can calculate gravitational potential energy by using the equation

GPE = m x 9.8

Which of the following devices does not make use of electrical energy?

upright piano

A bus engine transfers chemical potential energy into __ so that the bus moves

kinetic energy

In a nuclear fusion reaction, mass is transformed into

energy

According to the law of conservation of energy, the total amount of energy in the universe

remains constant

Work is a transfer of

energy

What is transferred by a force moving an object through a distance?

energy

The energy of motion is called

kinetic energy

An object's gravitational potential energy is not directly related to which of the following?

its speed

Which of the following is an example of an object with elastic potential energy?

all of the above

Why is the gravitational potential energy of an object 1 meter above the moon's surface less than its potenial energy 1 meter above Earth's surface?

the object's acceleration due to gravity is less on the moon

The gravitational potential energy of an object is always measured relative to the

reference level from which the height is measured.

Which of the following increases when an object becomes warmer?

thermal energy

The energy stored in gasoline is

chemical energy

The total potential an d kinetic energy of all the microscopic particles in an object make up its

thermal energy

Walking converts what type of energy into mechanical energy?

chemical

Nuclear power plants are designed to convert nuclear energy into what type of energy?

electrical

Solar cells convert what type of energy into electrical energy?

electromagnetic

Which of the following statements is true according to the law of conservation of energy.?

all of the above

If no friction acts on a diver during a dive, then which of the following statements is true?

KE + PE = KE + PE

the mechanical energy of an object equals its

kinetic energy plus its potential energy

The equation e=mc^2 relates energy and

mass

In which of the following does Einstein's famous equation apply?

nuclear fission and fusion reactions

Which of hte following statements is a consequence of the equation e=mc^2

all of the above

A drawback of solar energy is that it

depends on the climate

A benefit of a hydrogen fuel cell is that its byproduct is

water