Physics · PYQ NEET UG 2020
हिन्दीThe quantities of heat required to raise the temperature of two solid copper spheres of radii \( r_1 \) and \( r_2 \) (\( r_1 = 1.5 r_2 \)) through \( 1\text{ K} \) are in the ratio:
Correct answer · Option 4
\( \frac{27}{8} \)
Explanation
Heat required \( Q = ms\Delta T = V \rho s \Delta T = \frac{4}{3}\pi r^3 \rho s \Delta T \). Thus, \( \frac{Q_1}{Q_2} = (\frac{r_1}{r_2})^3 = (1.5)^3 = (\frac{3}{2})^3 = \frac{27}{8} \).