Question

The torque available at maximum power developed by the tractor is \(150\ \mathrm{N\,m}\). If the reserve torque is \(20%\), the peak torque that can be developed by the tractor (in \(\mathrm{N\,m}\)) is

• A. 100
• B. 120
• C. 180
• D. 210

Hint:

"Reserve torque" quantifies lugging ability: \(T_{\text{peak}} = (1+\text{reserve})\times T_{\text{rated}}\). A 20% reserve means the engine can deliver 20% more torque than at rated speed before stalling.

Answer 1

The Correct Option is C

Step 1: Recall definition of reserve torque.
Reserve torque (\(%\)) is the percentage by which the peak (maximum) torque exceeds the torque at rated speed (often the speed of maximum power): \[ \text{Reserve torque}=\frac{T_{\text{peak}}-T_{\text{rated}}}{T_{\text{rated}}}\times 100%. \]

Step 2: Plug values and compute.
Given \(T_{\text{rated}}=150\ \mathrm{N\,m}\) and reserve \(=20%\): \[ T_{\text{peak}} = T_{\text{rated}}\,(1+0.20) =150\times 1.20 =180\ \mathrm{N\,m}. \]

Final Answer:
\[ \boxed{180\ \mathrm{N\,m}} \]