Science MCQs

A vacuum flask keeps hot things hot and cold things cold by minimizing heat transfer.

When air heats up it expands becomes less dense and rises.

The black can absorbs more radiant heat so it heats faster.

Feathers trap air which is a poor conductor of heat.

Heated water expands becomes less dense and rises.

Cool dense air sinks from the AC pushing warm air up to be cooled.

Water molecules are not tightly packed reducing conductive heat transfer.

Vacuum lacks particles so it stops conduction and convection.

Black surfaces are good radiators so they release heat efficiently.

Solids transfer heat mainly by conduction due to vibrating particles.