A 10 kW drillingmachinein used for 5 minutesto bore a hole in an aluminium block of mass 10xx10^(3) kg . If 40% of the work done is utilised to raise the temperature of the block, find the rise in temperature of the aluminium block? (Specific heat of Aluminium =0.9Jkg^(-1)k^(-1))

A 10 kW drillingmachinein used for 5 minutesto bore a hole in an alumi

1.	A 10 kW drillingmachinein used for 5 minutesto bore a hole in an aluminium block of mass 10xx10^(3) kg . If 40% of the work done is utilised to raise the temperature of the block, find the rise in temperature of the aluminium block? (Specific heat of Aluminium =0.9Jkg^(-1)k^(-1))
Answer» Solution :Work done by the drilling machine in 5 minutes = W W = power `xx` time `=10xx10^(3) xx 5 xx60 = 3xx10^(6)`J The energy utilised to raise the TEMPERATURE of the block `=40% ` of `W = 3 xx 10^(6) xx (40)/(100)=12xx10^(5)J` Heat gained by ALUMINIUM block = MASS `xx` specific heat `xx` increase in temperature. `12xx10^( 5) =(10 xx 10^(3) ) xx 0.9 xx Deltat` `:.Deltat=(12xx10^(5))/(0.9xx10^(4) ) =133.3^(@)C`