Topic: Machine Design
A flat belt run over a pulley and transmitting the power of 2.5 KW. The linear velocity of the belt is 2.5 m/s. The angle of lap is 165 deg and the coefficient of friction between the belt and pulley is 0.3. If the initial tension of the belt is increased by 10%, what is the effect on power transmission? (neglecting the slip and centrifugal effect of the belt)
- A. The power transmission is increased by 10%
- B. The power transmission is reduced by 10%
- C. The power transmission is doubled
- D. The power transmission is reduced to half
Answer: A. The power transmission is increased by 10%
Explanation: Power transmitted P = (T1 - T2) * V. The ratio T1/T2 = e^(mu*theta) remains constant. The initial tension T0 = (T1 + T2)/2. If T0 is increased by 10%, both T1 and T2 increase proportionally by 10%. Consequently, the difference (T1 - T2) increases by 10%, leading to a 10% increase in power transmission.