Q.
A hammer of mass 200kg strikes a steel block of mass 200g with a velocity 8ms−1. If 23% of the energy is utilized to heat the steel block, the rise in temperature of the block is (specific heat capacity of steel = 460Jkg−1K−1)
Given, mass of hammer, m=200kg,
steel block of the mass =200g=0.2kg
and specific heat capacity of steel, s=460Jkg−1K−1
Velocity of hammer, v=8ms−1
As we know that, Kinetic energy, KE=21mv2
Putting the given values, we get =21×200×82=6400J
Hence, the 23% of this energy is converted to heat. ⇒H=1006400×23=1472J
The rise in temperature of steel, ΔT=msH=460×0.21472=16K
Hence, the rise in temperature is 16K.