A copper rod, 5m long when heated through 10c, expands by 1mm. If a second copper rod, 2.5m long is heated through 5c, by how much will it expand?
-
A.
4mm -
B.
0.25mm -
C.
2mm -
D.
0.12mm
Correct Answer: Option B
Explanation
l(_1) = 5m, ΔT = 10c, l(_2) – l(_1) = 1mm
l(_1) = 2.5m, ΔT = 5c, l(_2) – l(_1) = ?
| using | α | = | l(_2) – l(_1)
l(_1)ΔT |
| 1 5(10) |
= | l(_2) – l(_1)
2.5(5) |
| l(_2) | – | l(_2) | = | 2.5(5)
5(10) |
= | 1
4 |
= | 0.25mm |
There is an explanation video available below.