Ch 2.5 Water Power

Question 1

Kinetic energy

Answer 1

The form of energy that an object has when it is moving

Question 2

Potential energy

Answer 2

Energy that is stored and waiting to be used

Question 3

Hydroelectric power

Answer 3

Electricity produced by the kinetic energy of water moving over a waterfall or through a dam

Question 4

Compare and contrast the energy of moving water and the energy of water that is stored

Answer 4

Both moving and still water contain energy that can change in form.
The energy of moving water is kinetic energy; the energy of stored water is potential energy

Question 5

How does hydroelectric power plants work?

Answer 5

It captures the kinetic energy of moving water and change it to electrical energy:

1. Water is stored behind the dam with potential energy
2. Water flows through the penstocks, turns the turbine blades and produces mechanical energy
3. The turbine is connected to a generator, the turbine shaft turns the electromagnet and produce electrical energy

Question 6

Give 2 advantages of hydroelectric power

Answer 6

1. It does not pollute air

2. Water is free

Question 7

Give 2 disadvantages of hydroelectric power

Answer 7

1. A dam becomes a barrier across the river, wildlife habitats can be destroyed
2. Only certain locations can build a dam for hydroelectric power: need fast-moving water, and a valley behind the dam