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Name______Date: ______Class: _____

VOCABULARY: Unit 2- Mass, Force, and Motion

Definition
The ability to do work. / Important Notes
2 main kinds: potential and kinetic
subtypes: thermal, light, sound, nuclear, electrical, chemical
Examples
potential: a rock on a cliff
kinetic: a moving car
thermal: the heat from the sun
chemical: the food that you eat / Pictures


Definition
the transfer of energy to a body by the application of a force that causes the body to move in the direction of the force / Important Notes
Power is the rate at which work is done;
Machines are devices that help make work easier
Examples
Turning the page of a book.
Lifting a fork to eat.
Pushing a door open. / Pictures
Definition
the law that states that energy cannot be created or destroyed but can be changed from one form to another / Important Notes
The total amount of energy in a closed system is always the same.
Examples
A roller coaster transforming
potential energy into kinetic energy.
A light bulb transforming electricity into light and thermal energy. / Pictures

Definition
The energy of motion. / Important Notes
Kinetic energy = mass times volume squared
divided by two
KE= mv2
2
Examples
a moving car
a person running
a rock rolling down a hill / Pictures


Definition
the energy that an object has because of the position, shape, or condition of the object / Important Notes
Potential energy is equal to the mass times the gravity times the height or
P=mgh (same as weight times height or P=wh)
Examples
A big rock on top of a hill.
A rubber band that is stretched. / Pictures

Definition
the amount of work an object can do because of the object's kinetic and potential energies / Important Notes
Kinetic energy + potential energy = mechanical energy or
KE + PE = ME
Examples
The total energy of a ferris wheel
that is spinning.
The total energy of a car engine that is
running. / Pictures

Name______VOCABULARY: Unit 2- Mass, Force, and Motion (Continued)

Definition
the unit used to express energy / Important Notes
equivalent to the amount of work done by a force of 1 N acting through a distance of 1 m in the direction of the force (symbol, J)
Examples
1 joule = 1 Newton per meter or… / Pictures

Definition
the SI unit for force; the force that will increase the speed of a 1 kg mass by 1 m/s each second that the force is applied (symbol, N) / Important Notes
Named after famous scientist Sir Isaac Newton. 1kgm/s = 1 N
Examples
/ Pictures
Definition
a measure of the amount of matter in an object / Important Notes
Represented by the symbol “m”
Does NOT depend on gravity. You have the same mass on Earth as you do on the
Moon even though the gravity
Is different.
Examples
F=ma
PE=mgh
KE=1/2 mv2 / Pictures

Definition
a measure of the gravitational force exerted on an object; its value can change with the location of the object in the universe / Important Notes
Because the gravity is different on other planets, a person’s weight is not the same based on where they are located.
Mass is NOT the same as weight.
1 Newton = about .2 pounds
Examples
a person who weighs 200 lbs on
Earth, would weigh 75.4 lbs on
Mars
and 472.8 lbs on Jupiter! / Pictures

Definition
an action exerted on a body in order to change the body's state of rest or motion / Important Notes
Applied force makes something change or move.
Normal force is the force perpendicular to
The surface of contact.
F=ma
Examples
/ Pictures

Definition
a single force whose external effects on a rigid body are the same as the effects of several actual forces acting on the body
/ Important Notes
If the force is unbalanced, the object will move.
If the forces are balanced, the
object will not move and the net
force is zero.
Examples
/ Pictures

Name______VOCABULARY: Unit 2- Mass, Force, and Motion (Continued)

Definition
the tendency of an object to resist being moved or, if the object is moving, to resist a change in speed or direction until an outside force acts on the object / Important Notes
The more mass an object has, the more inertia it has.
Examples
when you slide forward when a
Car stops suddenly.
when you stay up when a roller coaster moves downhill suddenly. / Pictures

Definition
a force of attraction between objects that is due to their masses and that decreases as the distance between the objects increases / Important Notes
An object is in free fall only if gravity is pulling it down and no other forces are acting on it.
Gravity causes all objects to
accelerate toward Earth at a
rate of 9.8 m/s2.
Examples
A person skydiving.
Dropping your pencil.
The Earth orbiting around the Sun. / Pictures

Definition
the law that states that the force of attraction between two objects depends on the masses of the objects and the distance between the objects / Important Notes

Examples
/ Pictures

Definition
the force that opposes the movement of two surfaces that are in contact and are sliding over each other / Important Notes
Friction of moving things.
It is usually easier to roll round things than to slide them.
Examples
Using the brake on a bicycle.
Writing with chalk.
Scratching an itchy part of your skin. / Pictures


Definition
the force that resists the initiation of sliding motion between two surfaces that are in contact and at rest / Important Notes
Friction occurs because the surface of any object is rough
Examples
/ Pictures

Definition
the speed of an object in a particular direction / Important Notes
measured in m/s (meters per second)
A change in velocity is acceleration.
V=d/t
Velocity = distance
time
Examples
/ Picture

Definition
the rate at which velocity changes over time; an object accelerates if its speed, direction, or both change / Important Notes
F=ma is the formula for Newton’s 2nd Law of Motion.
The acceleration of an object depends on the
mass ofthe object and the
amount of force applied.
Examples
/ Pictures