MCQ!!! Part1

1. A small cork is fixed with wax to a metal plate. An electric heater is placed close to the plate. After a time, the waxmelts and the cork drops off.

How does heat reach the wax?

A by conduction only

B by conduction and convection

C radiation and conduction

D radiation and convection

2. Fibre is used for home insulation as shown

How does fibre prevent heat passing easily through the ceiling?

A Fibre allows air to pass through easily.

B Fibre is tightly packed

C Fibre is warm.

D Fibre traps air.

3. Which material is the best absorber of infra-red radiation?

A dark animal fur

B shiny metal

C window glass

D white paper

4. The diagram shows a metal saucepan containing water and
placed on a hot plate. After some time, the air at point X also
becomes hot.

What are the main ways by which heat travels from the hot
plate through the base of the metal saucepan' through the
water and through the air to Point X?
5. Density changes are responsible for which methods of thermal energy transfer?

A conduction only

B convection only

C radiation only

D conduction, convection and radiation