Physics

Question 1

Where does a muscular force come from?

Answer 1

It comes from the expanding and contracting of muscle tissue

Question 2

How is an elastic force produced?

Answer 2

It is produced by any bent or stretched object that returns to its original shape

Question 3

What does friction do?

Answer 3

Friction opposes motion whenever two surfaces are touching

Question 4

What is Gravity?

Answer 4

Gravity is the force of attraction between two objects

Question 5

Equal forces applied in opposite directions are said to be ____________ forces

Answer 5

Balanced

Question 6

An unbalanced force cause an object at rest to do what?

Answer 6

To start moving

Question 7

What does an unbalanced force cause

Answer 7

Acceleration

Question 8

What is a force

Answer 8

A Force is any cause of a change in motion

Question 9

What is an unbalanced force

Answer 9

A force that causes a change in motion

Question 10

Which forces are acting on a parked car

Answer 10

Gravity and gasses

Question 11

Who made observations about forces on moving or unmoving objects

Answer 11

Sir Isaac Newton

Question 12

What does the first law of motion states

Answer 12

• An object at rest remains at rest unless acted upon by an unbalanced force
• An object in motion continues to move at a constant speed in a straight line unless acted upon by an unbalanced force

Question 13

What is Inertia

Answer 13

The tendency of an object to oppose a change in motion

Question 14

What is a centripetal force

Answer 14

The inward force that keeps an object moving in a circle

Question 15

What are riding a bicycle you suddenly step on the brakes explain why you feel thrown back slightly

Answer 15

Because of inertia and because of an unbalanced force you have a change in speed and direction

Question 16

What is heat

Answer 16

A form of energy that usually results in a temperature rise in a substance or a object. OR
The energy transferred between material or parts of a material that have different temperature

Question 17

What are the sources of heat

Answer 17

Sun
Light
Television
Fire

Question 18

What is temperature

Answer 18

A measure of how hot or cold something is. OR

the measure of the average kinetic energy in an object

Question 19

What are three types of heat transfers

Answer 19

Conduction
Convection
Radiation

Question 20

What is conduction

Answer 20

The transfer of energy from molecule to molecule by collision

Question 21

What is Convection

Answer 21

The transfer of energy by the flow of a liquid to a gas

Question 22

What is Radiation

Answer 22

The transfer of energy by electromagnetic waves

Question 23

The flow within a fluid is due to the changes in density is called _________

Answer 23

Convection Current

Question 24

A furnace heats water to boil. The steam moves through baseboard types. Energy from the steam is transferred through the air In a room by ______and ______

Answer 24

Convection and radiation

Question 25

The effectiveness of heating systems depend on ___________

Answer 25

On the use of the insulating material such as foam helps to maintain heat

Question 26

You cannot measure heat directly but_________

Answer 26

You can measure the changes in temperature

Question 27

How much heat do substances that warm up slowly absorb

Answer 27

Large amounts for each degree the temperature rises

Question 28

When a substance cools off, it releases ________

Answer 28

Heat

Question 29

Substances that cool slowly use large amounts of heat for ___________

Answer 29

Each degree the temperature drops

Question 30

Each material has its own specific because

Answer 30

It takes different amounts of heat to change the temperature of equal masses of different substances

Question 31

What is specific heat measured in

Answer 31

Joules/Grams *C

Question 32

What is the formula for the amount of heat a substance absorbs

Answer 32

Mass x temperature x specific heat | M x 🔼t x cp

Question 33

What is the law of conservation

Answer 33

When you heat an object it gains energy. The heat loss and heat gain is because two or more substances are related

Question 34

What happens to the changes of state when a substance cools down

Answer 34

They are reversed

Question 35

What makes a material change its State?

Answer 35

Heat gain or heat loss

Question 36

When an ice cube reaches 0 degrees Celsius what happens

Answer 36

It keeps absorbing heat but the temperature stops rising

Question 37

Why does the temperature stop rising even though the ice is gaining heat

Answer 37

The ice cube melting the absorbed heat enables the molecules of the ice to breakaway form their crystal structure causing the Temperature not to rise until all of the ice is melted

Question 38

What is heat of fusion

Answer 38

The heat needed to change one gram of material from a solid to a liquid

Question 39

The heat needed to change one gram of a liquid into a gas is called

Answer 39

Heat of vaporization

Question 40

A blue flame gives more heat than a _____ flame

Answer 40

Yellow

Question 41

A bright yellow flame gives more light than a ______

Answer 41

Yellow flame

Question 42

What is a blue flame better for cooking than a yellow flame

Answer 42

Cooking with a big yellow flame means you are wasting fuel or gas since they carry less heat

Question 43

What is the heat of fusion and heat of vaporization for water, aluminum, Iron, Copper, Silver,mercury and lead

Answer 43

``` Water - 334, 2254 Aluminum -393, 10544 Iron-33, 6694 Copper-205, 4812 Silver-105.8, 2364 Mercury-11.8,295.4 Lead-22.9, 806 ```

Question 44

Force exert per unit area of surface

Answer 44

Pressure

Question 45

A gas exert a force on the wall is contained by

Answer 45

Gas expansion