Question

If a driven pulley is made at 350 rpm by a driving pulley of 0.3 m diameter running at 1400 rpm. Determine length of open belt when the pulleys are 4 meters apart.

(a) 10.50 m

(b) 10.40 m

(c) 10.30 m

(d) 10.20 m

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This is a very interesting question from Mechanical Power Transmission topic in section Mechanical Power Transmission of Farm Machinery

Answer 1

Correct answer is (b) 10.40 m

The best explanation: \(\frac{N2}{N1}=\frac{D1}{D2} \)

\(\frac{350}{1400}=\frac{0.3}{D2} \)

D2=\(\frac{0.3*1400}{350}\) = 1.2 m

L=2*4+\(\frac{π}{2} (0.3+1.2)+\frac{(0.3-1.2)^2}{4*4} \)

L = 10.40 m.