Physics · LAWS OF MOTION
हिन्दीA stone of mass \( 0.4\text{ kg} \) is tied to a light inextensible string of length \( 0.9\text{ m} \) and whirled in a horizontal circle on a smooth table top. If the string can withstand a maximum tension of \( 100\text{ N} \), the maximum linear speed with which the stone can be rotated without breaking the string is:
Correct answer · Option 2
15 m/s
Explanation
Centripetal force is provided by tension \( T = \frac{m v^2}{r} \). Setting \( T_{\max} = 100\text{ N} \): \( 100 = \frac{0.4 \times v_{\max}^2}{0.9} \implies v_{\max}^2 = 225 \implies v_{\max} = 15\text{ m/s} \).