Question

A block of mass 30.0 kg is being brought down by a chain. If the block acquires a speed of 40.0 $\frac{cm}{s}$ in dropping down 2.00 m, find the work done by the chain during the process.

• A. - 598 J
• B. 598 J
• C. -295
• D. 295

Answer 1

The correct option is A

- 598 J

So all the forces acting on the block are Tension and gravity

So applying work energy theorem for displacement 2 meters

$W_T+W_g=\Delta K.E$. ($W_r$ is the work done by Tension or work done by Chain)

$W_T+30\times 10\times 2cos{0}^{\circ }=\frac{1}{2}30\times (\frac{40}{100}{)}^2-\frac{1}{2}{30.0}^2$

$W_T+600=15\times 0.16$

$W_T=-597.6$

$W_T=-598J$