Science Form 3 chapter 6

The diagram shows how electrical energy is produced.

What does Q represent?

• The water is heated until steam is produced and the turbine is rotated.

• The water rotates a motor, which will then rotate a generator.

• A mixture of steam and gas is heated until they expand and the turbine is generated.

• The water rotates a turbine, which will then rotate a generator.

Which of the following describe the characteristics of non-renewable energy sources?

• Can be depleted if the usage is not controlled

• Takes millions of years to be formed

• Can not cause environmental pollution

• Have limited sources

The diagram shows an apparatus.

Which of the following statements are true about the apparatus?

• It is used to change a low input voltage to a higher output voltage

• It alters the voltage of alternating current

• It is used to change a high input voltage to a lower output voltage

• It helps to reduce energy wastage during the transmission of electrical energy

The diagram shows four transformers, A, B, C and D.

Which transformer is a step - up transformer?

• A

• B

• C

• D

Where does the electric power voltage begin to be lowered in the electricity transmission and distribution system?

• Substation

• National power grid

• Switch field

• Main substation

The electrical wiring system in a home has several safety features.

Which of the following are the safety features?

• The main fuse

• The colour codes for different wires

• The Earth Leakage Circuit Breaker

• Electric meter

The diagram shows a common electrical device.

What are the safety features shown in the device.

• Live wire

• Earth wire

• Neutral wire

• Fuse

An electrical appliance is marked 800 W, 240 V.

What is the cost of using the appliance for four hours daily for a week if the cost of a unit of electricity is RM 0.20?

• RM 3.30

• RM 4.48

• RM 50.64

• RM 205.23

An electric iron is rated 1050 W, 240 V.

Which of the following is a suitable fuse rating for the iron?

• 1 A

• 2 A

• 3 A

• 5 A

The statements are about a type of energy source.

What is the energy source?

• Nuclear

• Water

• Geothermal

• Sun