Question

A copper block of mass 1kg slides down one rough inclined plane of inclination `37^(@)` at a constant speed. Find the increase in the temperature of the block as it slides down temperature of the block as it slides down through 60cm assuming that the loss in mechanical energy goes into the copper block as thermal energy. (specific heat of copper=`420Jkg^(-1)K^(-1),g=10ms^(-2)`)
A. `6.6xx10^(-3).^@C`
B. `7.6xx10^(-3).^(@)C`
C. `8.6xx10^(-3).^(@)C`
D. `9.6xx10^(-3).^(@)C`

Answer 1

Correct Answer - C
`(1)/(2)mv^(2)=mSDeltaT`, But `(1)/(2)mv^(2)=mgh`
`rArrV^(2)=2gl sin theta,(1)/(2)xx2gl sin theta=SDeltaT`