Generation and transmission of electricity

Question 1

What is electric current?

Answer 1

The flow of charge round a circuit

Question 2

Does alternating change direction?

Answer 2

Yes

Question 3

Does direct current change direction?

Answer 3

No

Question 4

What induces a voltage?

Answer 4

Moving a magnet in a coil of wire

Question 5

What are the 4 factors that affect the size of the induced voltage +current

Answer 5

1. Strength of magnet
2. Number of turns in coil
3. Area of coil
4. speed of movement

Question 6

What are the 6 alternatives to burning fossil fuels?

Answer 6

1. Hydroelectricity
2. Wave power
3. Tidal power
4. Wind power
5. Solar power
6. Geothermal energy

Question 7

What is hydroelectricity?

Answer 7

Building dams and flooding valleys

Question 8

What is wave power?

Answer 8

Wave powered turbines

Question 9

What is tidal power?

Answer 9

Using moon+ suns gravity

Question 10

What is wind power?

Answer 10

Wind turbines

Question 11

What is solar power?

Answer 11

Electrical current from sunlight

Question 12

What is geothermal energy?

Answer 12

Heat from underground

Question 13

Why do renewable resources usually have the lowest running costs?

Answer 13

1.Because there is no fuel involved( except biomass)

Question 14

What two types of renewable resources effect the surrounding habitats?

Answer 14

1. Hydroelectric

2. Tidal

Question 15

How does hydroelectricity work?
How does it impact the environment?
What’s an advantage of it?

Answer 15

1. Involves flooding a valley by building a big dam
2. Rainwater is caught and goes out through turbines
3. Big impact on environment due to valleys flooding and possible loss of habitat
4. Big advantage is that its a n immediate response to electricity demand- more water let out through turbines to make electricity

Question 16

How does wave power work?

Whey are they unreliable?

Answer 16

1. Waves provide up and down motion which drives generator

2. Wave power unreliable, because waves die out when wind drops

Question 17

How do tidal barrages work?

Answer 17

1. Big dams across river estuaries, with turbines in them

2. As tide comes in fills up estuary, this water allowed out of turbines

Question 18

How do wind turbines work?

What are the disadvantages?

Answer 18

1. Each turbine has own generator so electricity made directly from wind turning the blades, which turn the generator
2. Spoil the view
3. Noisy
4. Only work when its windy

Question 19

How does Geothermal energy work?

What is a drawback of Geothermal energy?

Answer 19

1. Water pumped down to hot rocks, returns as steam to drive generator
2. Big setup costs

Question 20

What does a step up transformer do?

Answer 20

Increase voltage, decrease current

Question 21

What does a step down transformer do?

Answer 21

Decrease voltage, increase current

Question 22

What is risk with flying a kite next to a power line?

Answer 22

1. Electrocution due to high voltage