In the arrangements, A and B shown in Figure 4.7, pins P and Q are fixed to a metal loop and an iron rod with the help of wax. In which case are both the pins likely to fall at different times? Explain.

Question

Philoid · Accepted Answer

In fig B, pins are likely to fall apart at a different time while in fig A, pins will nearly fall at the same time.

Heat travels in the solid by conduction, in fig B we see that point P is closer to heat and then point Q, so the heat that travels in the rod will reach P first and after some time it will reach point Q.

While in fig A, heat will reach the points P and Q simultaneously since both points are located at the same distance from burning candle.