Question

To obtain 200 kg m of torque at the transmission output shaft, what gear ratio would be necessary? (Assume transmission efficiency 90% and input torque as 20 kg m)

(a) 1:9

(b) 1:10

(c) 1:11

(d) 1:12

I had been asked this question in unit test.

I'd like to ask this question from Mechanical Power Transmission in chapter Mechanical Power Transmission of Farm Machinery

Answer 1

Correct answer is (c) 1:11

To elaborate: Torque of transmission input shaft = i/p torque * efficiency = 20*\(\frac{90}{100}\) = 18 kg m

Gear ratio = \(\frac{18}{200}\) = 1:11.