Four materials are tested in a thermal-conduction rig. Each sample has the same area and thickness, and the temperature difference across each sample is kept the same. The energy transferred through each sample in one second is recorded.
| Material | Energy transferred in one second (J) |
|---|---|
| P | 8 |
| Q | 18 |
| R | 4 |
| S | 12 |
Which material has the greatest thermal conductivity?
Material R
Material Q
Material P
Material S