Question

A differential band brake is shown in figure. The width and thickness of the steel band are 100 mm and 3 mm, respectievly and the maximum tensile strees in band is 50 MPa. the coefficient of friction between the friction lining and the brake drum is 0.25. The tensions in the band are

• A. 15 nK, 5.26 kN
• B. 18 kN, 6.82 kN
• C. 25 kN, 8.78 kN
• D. 22 kN,. 7.89 kN

Answer 1

The correct option is A 15 nK, 5.26 kN

$T_1={\sigma }_{max}\times \text{area}$

$=50\times 100\times 3=15kN$

$\frac{T_1}{T_2}=e^{\mu \theta }$

$\frac{15}{T_2}=e^{(0.25\times 4\pi /3)}$

$T_2=5.26kN$