physics
posted by bob .
The Weistin Stamford Hotel in Detroit is 228 m tall. Suppose a piece of ice which initially has a temperature of o degrees celcius falls from the hotel roof and crashes to the ground. Assuming that 50% of the ices mechanical energy during the fall and collision is absorbed by the ice and that 3.33 x 10^5 Joules is required to melt 1 kg of ice calculate the fraction of ice's mass that would melt.

Compute the potential energy release of the fall (Hint: PE = Mgh). The mass M will remain as an unknown variable. Multiply that by 0.5 for the heat release. Divide the result by the heat of fusion (33.5*10^5 J/kg x M)
The mass M will cancel out, and you will have the fraction that melts.