Question

A copper cube of mass $200g$ slides down on a rough inclined plane of inclination 37${}^o$ at a constant speed. Assume mechanical energy goes into the copper block as thermal energy. Find the increase in temperature of the block as it slides down through $60cm$. Specific heat capacity of copper is $420Jk{g}^{-1}{K}^{-1}$

• A. ${0.86}^{o}C$
• B. ${0.086}^{o}C$
• C. ${0.0086}^{o}C$
• D. none

Answer 1

The correct option is C ${0.0086}^{o}C$

$E=mgh$
$=0.2\times 10\times \left(0.36\right)=0.72J$
$E=mC\Delta \theta =0.72$
$\Delta \theta =\frac{0.72}{420\times 0.2}=8.6\times {10}^{-3}$ ${}^o$$C$