Science Review Chapter 7 and 8

Question 1

Thermal energy:

Answer 1

the total kinetic energy in an object

Question 2

Temperature:

Answer 2

A measure of the average kinetic energy of the particles of a substance.

Question 3

Heat transfer:

Answer 3

The transfer of energy from the particles of a warmer object to the particles of a cooler object.

Question 4

Particle theory of matter:

Answer 4

A theory that explains what matter is made of, and how it behaves.

All matter is made up of tiny particles

Particles are always moving

Particles have tiny spaces between them

Particles attract each other

As the temperature increases the particles move faster

Question 5

Thermal Conduction:

Answer 5

the transfer of heat through direct contact between objects or substances

Question 6

Thermal Expansion:

Answer 6

An increase in the volume of a substance caused by heating

Question 7

Thermal contraction:

Answer 7

a decrease in the volume of a substance caused by heating

Question 8

What happens to particles when an object gains thermal energy?

Answer 8

When particles gain thermal energy, they start to move faster. This is also mentioned in the particle theory.

Question 9

Does an object gain or lose energy when freezing?

Answer 9

When an object freezes the object loses energy and the particles start to slow down.

Question 10

Does thermal expansion change an object’s mass?

Answer 10

Thermal expansion does not change an object’s mass because it has more to do with volume and density.

Question 11

What does temperature actually measure?

Answer 11

Temperature actually measures the average kinetic energy of the molecules within a substance.

Question 12

Which direction does thermal energy move?

Answer 12

Thermal energy moves from a range of higher temperatures to lower temperatures.

Question 13

Why do particles move more when heated?

Answer 13

Particles move more when heated because they gain kinetic energy causing them to move faster.

Question 14

Why does tire pressure increase after riding a bike?

Answer 14

Tire pressure increases after riding due to heat generated from friction between the tire and the road.

Question 15

Which type of matter expands the most when heated?

Answer 15

Gases expand the most when heated.

Question 16

Explain why most objects expand when heated using particle theory.

Answer 16

According to particle theory, all matter is made up of tiny particles that are constantly moving. When an object is heated, these particles absorb energy, causing them to move faster. As the particles move faster, they spread further apart, increasing the space between them. This results in the expansion of the object.

Question 17

A door seems smaller in winter than in summer. Why?

Answer 17

A door seems smaller in the winter than the summer because it shrinks because of the lower humidity and colder temperatures.

Question 18

conduction:

Answer 18

The transfer of thermal energy through touch

Question 19

geothermal energy:

Answer 19

Energy contained below earth’s surface

Question 20

igneous rock:

Answer 20

Rock formed by magma that is cooled and solidified

Question 21

metamorphic rock:

Answer 21

Formed when heat and pressure changes the existing rock

Question 22

convection:

Answer 22

Movement of energy through fluids (Liquids/gases)

Question 23

radiant energy:

Answer 23

Energy that travels in a form of electromagnetic waves through empty space

Question 24

radiation

Answer 24

The transfer of radiant energy through electromagnetic waves

Question 25

Insulation

Answer 25

Reduces energy transfer

Question 26

Can conduction occur without matter?

Answer 26

No, conduction cannot occur without matter. Matter is a very important part of conduction, which is through touch.

Question 27

What causes convection in the atmosphere?

Answer 27

Convection is caused in the atmosphere by thunderstorms. Thundersotrms happen when the Earth's surface is not evenly heated.

Question 28

What happens when UV hits human skin?

Answer 28

When UV hits human skin our skin is to absorb the energy, this could make our skin feel hot, if too hot we can burn.

Question 29

What is conduction?

Answer 29

The transfer of energy through touch

Question 30

Match the energy to the transfer type: Hamburger cooking in a pan, Stew boiling, Sunlight reaching earth.

Answer 30

Hamburger cooking in a pan-conduction Stew boiling-convection Sunlight reaching earth- radiation

Question 31

Which object heats up most by sun? Black plastic, or white paper?

Answer 31

Black plastic because black plastic absorbs more radiation, leading to a warmer object

Question 32

Where does convection occur best; air, ice, metal, or plastic?

Answer 32

Air because the thermal energy can be transferred from one area to another, while the rest are plastic

Question 33

Give a scenario showing conduction

Answer 33

A hot curling iron is near your hand, and you feel your hand getting warmer

Question 34

How is conduction different from convection?

Answer 34

Convection is the movement of energy through fluids like liquid and gas, while conduction is the transfer of energy through touch.