Students compare how effectively four rods made from different materials, W, X, Y and Z, transfer thermal energy. All four rods have the same size and shape. Wax is used to attach a pin to one end of the first rod. When it gets warm, the wax melts. The opposite end of the rod is heated, and the time for the pin to drop off is measured. This procedure is carried out again for each rod. The students then draw a graph of the time taken for each pin to fall. Which statement is correct?
- AX is a better thermal conductor than Y.
- BY is a better thermal conductor than W.
- CZ is a better thermal conductor than W.
- DZ is a better thermal conductor than X.