Question

Mintu wants to increase the heat transfer between a metal iron and another piece of metal he wants to shape. He decides to increase the time the two metals are in contact, use a larger metal iron, and use a new metal material with a higher specific heat.

Where is Mintu's error?

Mintu should have decreased the size of the metal iron.
Mintu should have decreased the time he touches the two metals.
Mintu should have chosen a material with a lower specific heat.
Mintu should have chosen a material the same temperature as the iron.

Answer 1

Mintu's error is the third choice — he should have chosen a material with a lower specific heat.

Reason: increasing contact time and using a larger iron both increase heat transfer. But a target material with lower specific heat requires less energy to raise its temperature, so it heats up more for the same heat input; choosing a higher specific heat would make it harder to heat.