Question

If a driven pulley is made to rotate at 350 rpm by a driving pulley of 0.3 m diameter, running at 1400 rpm, what will be the length of open belt drive when the pulleys are 2 m apart?

(a) 7.14 m

(b) 6.45 m

(c) 8.88 m

(d) 10 m

I got this question in quiz.

I want to ask this question from Power Transmission System in section Ignition and Power Transmission of Farm Machinery

Answer 1

The correct answer is (b) 6.45 m

For explanation: N1D1 = N2D2

1400 * 0.3 = 350 * D2

D2 = 1.2 m

Length of open belt drive = 2C + \(\frac{[π(D1+D2)]}{2}+\frac{(D1-D2)^2}{4C} \)

= 2*2 + \(\frac{[π(1.5)]}{2}+\frac{(0.9)^2}{8} \)

= 6.45 m