1P January 2014

Question 1

How does insulation prevent energy loss by conduction?

Answer 1

Fibres are good insulators, air is a bad conductor, conduction requires solids.

Question 2

How does insulation prevent energy loss by convection?

Answer 2

Reduces formation of convection currents as the air in the insulation cannot move.

Question 3

What is a virtual image?

Answer 3

Cannot be formed on a screen. Image formed by extension of light rays.

Question 4

Difference between transverse and longitudinal waves?

Answer 4

Transverse - vibrations are perpendicular to direction of energy transfer.
Longitudinal - vibrations are the same direction as the direction of energy transfer.

Question 5

What is meant by elastic behaviour?

Answer 5

Returns to original length when force is removed.

Question 6

What effect does the emission of a beta particle have on a nucleus?

Answer 6

Neutron number decreases by 1. Proton number increases by one, as the neutron turns into a proton.