Question

A metal wire of length 0.5 m and cross-sectional area 10–4 m2 has breaking stress 5 × 108 Nm–2. A block of 10 kg is attached at one end of the string and is rotating in a horizontal circle. The maximum linear velocity of block will be _____ ms–1

Answer 1

A=10–4m2
l=$\frac{1}{2}$m
σ=5×108
$\frac{mv^2}{la}=5×10^8$
$v=\sqrt{\frac{5×10^8×\frac{1}{2}×10^{−4}}{10}}$
v=5×10=50 m/s
So, the answer is 50 m/s.