A hail at 0oC falls from a height of 1 km on an insulated surface and its whole kinetic energy is converted into heat. What fraction of it will melt ?
Heat energy required to melt 10 kg ice at its melting point will be _____. (The latent heat of fusion of water = 333.55 kJ kg−1).
A lead bullet penetrates into a solid object and melts. Assuming that 50% of its kinetic energy was used to heat it, calculate the initial speed of the bullet. The initial temperature of the bullet is 27∘C and its melting point is 327∘C. Latent heat of fusion of lead = 2.5 × 104 J kg−1 and specific heat capacity of lead = 125 J kg1 K1.