Forms of energy and heat transfer

Question 1

What are the different forms of energy?

Answer 1

1) sound energy
2) chemical energy
3) light energy
4) thermal energy
5) kinetic energy
6) potential energy
7) electrical energy

Question 2

Sound energy is given out when an object (1).

Answer 2

1) vibrates

Question 3

(1) stores chemical energy. We need the chemical energy stored in (1) to help us (2).
(3) , such as (4) also store chemical energy. When they are (5), the chemical energy stored in them is released as (6).
(7) store chemical energy too. They can provide energy for (8).

Answer 3

1) food
2) stay alive, grow and carry out our activities
3) fuels
4) wood, charcoal and petrol
5) burned
6) other forms of energy
7) batteries
8) small electrical appliances and other devices

Question 4

(1) gives out light energy. Some (2), such as (3), also give out light energy. The (4) give out light energy too. Light enables us to (5). (6) need light to (7).

Answer 4

1) the Sun
2) living things
3) fireflies
4) lamps, televisions and projectors
5) see things
6) plants
7) make food

Question 5

(1) gives out thermal energy. (2) also give out thermal energy. The (3) an object, the more thermal energy it gives out.

Answer 5

1) the Sun
2) electric irons, electric heaters and the flame of gas stoves
3) hotter

Question 6

All (1) have kinetic energy. For example, (2) has kinetic energy. The amount of kinetic energy of an object is related to its (3).
The (4) an object moves, the more kinetic energy it has.
The (5) the (6) of an moving object, the more kinetic energy it has.

Answer 6

1) moving objects
2) a running man or a moving car
3) speed and mass
4) faster
5) greater
6) mass

Question 7

An object gains potential energy when it is (1). The (2) the (3) of the object, the more potential energy it has.
Some objects also store potential energy when they are (4).

Answer 7

1) raised to a higher position
2) higher
3) position
4) stretched or compressed

Question 8

Electrical energy is the (1) at home. All (2) need electrical energy to work. Electrical energy is usually (3) from (4) and then (5) to our homes along (6). It can also be obtained from (7).
We can also (8) electrical energy in (9). For example, (10) carries electrical energy. Some (11) can (12) electrical energy to (13).

Answer 8

1) most widely used energy form
2) electrical appliances
3) supplied
4) power stations
5) transmitted
6) power cables
7) batteries
8) observe the presence of
9) Nature
10) lighting
11) animals
12) generate
13) protect themselves

Question 9

Energy can be measured in different (1). We can measure energy in (2). One (3) represents a very (4) amount of (5). We use (6) as the (7) for a (8) amount of energy. One (9) equals to (10)(2).
A (11) is another (12). This (13) is commonly used for (14). For a (8) amount of energy, we use (15) as the (13). One (15) is equal to (10)(11).

Answer 9

1) units
2) joules
3) joule
4) small
5) energy
6) kilojoules
7) measuring unit
8) larger
9) kilojoule
10) 1000
11) calorie
12) unit of energy
13) unit
14) measuring the energy value of food
15) kilocalories

Question 10

The (1) of (2) states that energy can be (3), but it cannot be (4).

Answer 10

1) law
2) conservation of energy
3) converted from one form into another
4) destroyed or created

Question 11

In a (1), the (2) of the arrows are (3) to the (4) they (5).

Answer 11

1) Sankey diagram
2) widths
3) proportional
4) amount of energy
5) represent

Question 12

In (1), we often use (2) to (3) into (4). Such (2) are (5).
The (6) of an (7) is a (8) of (9).
What is the formula for calculating (6)? (10)

Answer 12

1) daily life
2) devices or appliances
3) convert energy from one form
4) another form of useful energy
5) energy converters
6) efficiency
7) energy converter
8) measure
9) how much energy input is converted into useful energy output
10) useful energy output / total energy input x 100%

Question 13

What is heat?

Answer 13

The energy transferred from a hotter object to a colder one.

Question 14

When food is cooked on a hot plate, heat is (1) from the (2) to the (3). This (4) is called (5). (5) requires a (6) such a (7) to (8).
(5) can take place in (9). It can also take place (10). Heat can be (11) by (5) through (9) from (12) to (13).
Some (14)(15) heat (16) than others. (17) such as (18)(15) heat (19). They are (20). In general, (21)(15) heat more (22). They are (23). (23) are also called (24). (25) are (23).

Answer 14

1) heat
2) hot plate
3) food
4) process of heat transfer
5) conduction
6) medium
7) a solid, a liquid or a gas
8) transfer heat
9) an object
10) between two objects that are in contact
11) transferred
12) the hotter end
13) the colder end
14) materials
15) conduct
16) faster
17) metals
18) copper and iron
19) fast
20) good conductors of heat
21) non-metals
22) slowly
23) poor conductors of heat
24) insulators of heat
25) water and air

Question 15

(1) conduct heat very slowly. Rather than conduction, heat (2) in (1) by another (3).
When the water at the left bottom corner of the convection tube is (4), the (5)(6). At the same time, the (7) in the tube (8) to (9). This movement of water forms a (10) of water.
Convection in gases takes place in the same way as in liquids. When the (11) the candle flame gets (12), it (6). The (13)(8) to (14). The (15) of the air forms a (10) of air. Similar to conduction, convection requires (16) to (17). However, convection can take place only in (1). It cannot take place in (18).

Answer 15

1) liquids and gases
2) is transferred
3) process
4) heated
5) hot water
6) rises
7) cold water
8) sinks
9) take the place of the risen hot water
10) convection current
11) air above
12) hot
13) cold air from the surroundings
14) take the place of the hot air
15) movement
16) medium
17) transfer heat
18) solids