[3 Mark Question Answer]

Question 13 Marks

What social initiatives must be taken for the sensitive use of energy?

Answer

The following social initiatives need to be taken:

Public awareness can be improved through mass-media and children's participation in campaigns and eco-club activities.
Community involvement need to be done to reduce the misuse of electricity.
NGO's can be used to create social awareness of the sensitive use of resources.

Question 23 Marks

Describe three ways for the efficient use of energy.

Answer

Three ways to use energy efficiently:

The use of compact fluorescent lights (CFL) saves 67% energy and may last 6 to 10 times longer than the incandescent lamps.
The use of advanced boilers and furnaces in industry can save sufficient amount of energy in attaining high temperatures while burning less fuel. Such technologies are more efficient and less polluting.
The fuel efficiency in the vehicles can be increased by reducing the weight of the vehicle, using the advanced tyres and computer controlled engines.

Question 33 Marks

State three differences between the primary and secondary cells.

Answer

Primary Cell	Secondary cell
1. Chemical reaction is irreversible. 2. Only chemical energy is converted into electrical energy when current is drawn from it. 3. It cannot be recharged and its internal resistance is high.	1. Chemical reaction is reversible. 2. It converts electrical energy into chemical energy when current is passed in it (i.e., during charging), while converts chemical energy into electrical energy when current is drawn from it (i.e., during discharging). 3. It can be recharged and its internal resistance is low.

PHYSICS [3 Mark Question Answer]