engineering recuitment GATE IN Test Series 2023-24 Mock Test Sensors and Industrial Instrumentation Measurement of Torque
A shaft is to transmit power up to 44 kW at a constant speed of 25 rps and it is proposed that the torque be sensed by a pair of torque strain gauges bonded to a specially machine portion of the shaft. The gauges are to be connected push pull in an equiarmed voltage sensitive bridge, the output of which is to be calibrated in power units. If the maximum strain value of the gauges is 0.0015, their resistance 120 Ω and gauge factor 2.1, calculate the diameter of steel shaft to which they should be bonded if its modulus of elasticity is 200 × 109 N/m2.
1
16.8 mm
2
8.4 mm
3
33.6 mm
4
44.2 mm