A rod of length
\(l\) and negligible mass is suspended at its two ends by two wires of steel (wire
\(A\)) and aluminium (wire
\(B\)) of equal lengths (figure). The cross-sectional areas of wires
\(A\) and
\(B\) are
\(1.0~\text{mm}^2\) and
\(2.0~\text{mm}^2\) respectively.
\((Y_{\text{Al}}=70\times10^9~\text{N/m}^2\) and
\(Y_{\text{steel}}=200\times10^9~\text{N/m}^2)\)
| (a) |
The mass \(m\) should be suspended close to wire \(A\) to have equal stresses in both wires. |
| (b) |
The mass \(m\) should be suspended close to \(B\) to have equal stresses in both wires. |
| (c) |
The mass \(m\) should be suspended in the middle of the wires to have equal stresses in both wires. |
| (d) |
The mass \(m\) should be suspended close to wire \(A\) to have equal strain in both wires. |
The correct statements are:
| 1. |
(b), (c) |
3. |
(b), (d) |
| 2. |
(a), (d) |
4. |
(c), (d) |
