Newt needs to melt some ice, so he fires a test projectile (0.025 kg) at 30.0 degrees C at a speed of 240 m/s into a large block of ice at 0 degrees C, in which it becomes embedded (comes to rest). Approximately what mass of ice melts? (i.e. ignore the heat lost by the projectile in going from 30-0 degrees C).
The Attempt at a Solution
The heat of fusion of water is 3.35x10^5J.
e=(0.025 * 240^2)/2=720J
720J/3.35x10^5J=0.002, so 0.002kg of ice melts.
I get the feeling that's incorrect, especially since I didn't do anything with the temperature (although it mentions that I should ignore the heat lost by the projectile).
Thanks for any help you can provide.