Question

A block of mass 1 kg slides down on an inclined plane with the angle of inclination of ${30}^0$. Find the work done as the block slides through 50 cm.

• A. 3.45 J
• B. 5.30 J
• C. 2.45 J
• D. 4.50 J

Answer 1

The correct option is C 2.45 J

The force component $mg\cos {30}^{\circ }$ and N balance each other and the body comes down because of the force component $mg\sin {30}^{\circ }$ applied to it.

$W=\overrightarrow{F}.\overrightarrow{S}=mg\sin 30°\times 50\times {10}^{-2}=1\times 9.8\times \frac{1}{2}\times 50\times {10}^{-2}=245\times {10}^{-2}=2.45J$