Question

Shaft power measurement of a rotating shaft is to be carried out by measuring the angular velocity and torque. The power consumed was 5.5 kW at constant angular velocity. The velocity measured using variable reluctance type tachometer. If the counter of the tachometer indicates 1000 pulses in 10sec and the tachometer wheel is having 60 teeth then the developed torque in the shaft in (N-m) approximately is __________.

• A. 525.211

Answer 1

The correct option is A 525.211
$Speed=N=\frac{P}{T}\times 60$

$P=\frac{Pulse}{sec}=\frac{1000}{10}=100$

$T=teeth=60$

$\therefore N=100rpm$

$Power\left(P\right)=\frac{2\pi NT}{60}=5.5kN$

$T=\frac{5.5\times {10}^3\times 60}{2\pi \times 100}$

$T=525.211N.m$