Question

For the block brake shown in figure, The braking torque is _____. If the coefficient of friction is 0.35 and the drum rotates in clockwise direction .

• A. 0.5 kN-m
• B. 0.2 kN-m
• C. 3 kN-m
• D. 1 kN-m

Answer 1

The correct option is B 0.2 kN-m


$\text{Taking moment about O}$

$N\times 20=F\times 60$

$N\times 20=1\times 60$

$N=3kN$

$\text{Braking torque =}f\times r$

$\text{= 0.35}\times \text{3}\times \text{0.2 = 0.2 kN - m}$