Physics

Question 1

Force

Answer 1

a push or pull

• causes objects to change speed or directions
• object only accelerates when forces are unbalanced
• forces are represented by arrows
• size of arrow = strength of force
• direction of arrow = direction of force

Question 2

Force Diagrams

Answer 2

• gravity is always down
• normal force is perpendicular to the surface
• net force is all forces added together
• shows the direction of acceleration
• friction is opposite the direction of motion

Question 3

Friction

Answer 3

a force that opposes motion

• caused by rough surfaces of all materials
• friction results in heat
• effects of friction
• spinning
• curving
• slowing

Question 4

4 Types of Friction

Answer 4

1. sliding - when solid objects grind over each other
2. rolling - turning over and over on an axis
3. fluid - when liquids or gas slow the motion of a solid
4. static - the friction between two solids that aren’t moving

Question 5

Newton’s 1st Law

Answer 5

an object in motions tends to stay in motion and an object at rest tends to stay at rest until acted on by an outside force

Question 6

Inertia

Answer 6

a property of matter that resists a change in motion

-objects with great mass have high inertia

Question 7

Newton’s 2nd Law

Answer 7

unbalanced forces make objects accelerate

force = mass x acceleration

Question 8

Newtons 3rd Law

Answer 8

for every action there is an equal and opposite reaction

Question 9

Energy

Answer 9

the ability to do work

Question 10

Mechanical Energy

Answer 10

energy related to motion

- PE + KE = Mechanical Energy

Question 11

Potential Energy

Answer 11

stored energy that can be released to do work

Question 12

Chemical Energy

Answer 12

the energy required to bond atoms together

• building bonds uses energy
• breaking bonds releases energy

Question 13

Elastic Potential Energy

Answer 13

energy associated with objects that can be stretched or compressed

Question 14

Work

Answer 14

• transfer of energy

- power = rate at which work is done

Question 15

Kinetic Energy

Answer 15

energy an object has due to its motion

-depends on mass and velocity

Question 16

Gravitational Potential Energy

Answer 16

energy that’s stored in objects that are high off the ground

Question 17

Thermal Energy

Answer 17

the internal motion of atoms

• rapid motion - high energy
• slow motion - low energy

Question 18

Electromagnetic Energy

Answer 18

the energy of moving electric charges

• electricity
• infrared and ultraviolet radiation
• (sun)light
• radio waves

Question 19

Nuclear Energy

Answer 19

the energy that is created by building or breaking the nuclei of atoms

• creates lots of heat
• stored in nucleus
• released during nuclear reactions

Question 20

Fission

Answer 20

breaking nuclei into smaller atoms

-means “to cut”

Question 21

Law of Conservation of Energy

Answer 21

energy cannot be created or destroyed, only changed from one form to another

Question 22

Electrical Energy

Answer 22

energy of electric charges

-can be either PE or KE

Question 23

Single Transformations

Answer 23

one form of energy being transformed to get work done

Question 24

Multiple Transformations

Answer 24

a series of energies being transformed to get work done

Question 25

Energy Relationships

Answer 25

1. Friction and Energy
   friction transforms mechanical energy to thermal energy
2. Energy and Matter
   matter can be transformed to energy

Question 26

Acceleration

Answer 26

a change in velocity