Question 2.9: During a hailstorm, a stone, at a height of 2.50 km has mass......

Engineering Thermodynamics [1393131]

During a hailstorm, a stone, at a height of 2.50 km has mass 3 g. What is its potential energy? If all this potential energy is converted to latent heat during the fall, calculate the mass of the hailstone on reaching the ground. Take the specific latent heat of fusion of ice to be $3.36 \times 10^5 J/kg$ .

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PE = mgh = 0.003 × 9.81 × 2500 = 73.58 J

m · L = 73.58, where m is the mass of hail stone melted and L is the latent heat of fusion.

Therefore, melted mass = $21.9 × 10^{–2} g$
Remaining mass that reaches the ground = $3 – 21.9 × 10^{–2} = 2.781 g$

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