Question

The power transmitted by a 75 mm diameter shaft at 140 r.p.m., subjected to a maximum shear stress of $60N/m{m}^2$, is nearly

• A. 68 kW
• B. 70 kW
• C. 73 kW
• D. 76 kW

Answer 1

The correct option is C 73 kW

D = 75 mm
N = 140 rpm

${\tau }_{max}=60N/m{m}^2$

$\Rightarrow {\tau }_{max}=\frac{T}{Z_p},P=\frac{2\pi NT}{60}$

$\Rightarrow {\tau }_{max}=60\times \frac{\pi \times {75}^3}{16}$

$\Rightarrow P=\frac{2\pi \times 140\times 60\pi \times {75}^3}{16\times 60}$

= 73.8 kW