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1. A lead bullet initially at 17oC just melts upon striking a target. Assuming that all of the initial kinetic energy of the bullet goes into the internal energy of the bullet to raise its temperature and melt it, calculate the speed of the bullet upon impact

I know KE = 1/2 mv^2 and Q= mcdeltaT

In this case, Q= 1/2mv^2

so that mcdeltaT = 1/2mv^2

This way the masses cancel and so cdeltaT = 1/2v^2 and the c of lead is 128.

I know the initial temperature is 17 degrees, but what is the final temperature? The wording of the question is confusing me and I don't know what delta T is. It seems like such a trivial mistake.

2. A cube of ice is taken from the freezer at -10oC and placed in a 110 g aluminum calorimeter filled with 280 g of water at a temperature of 25oC. The final situation is observed to be all water at 11oC. What was the mass of the ice cube?(cwater=4186 J/kg.oC, cal=900 J/kg.oC, cice=2000 J/kg.oC, Lf=33.5x104 J/kg)

I know Q gained = Q lost

The aluminum in this case is providing the energy, thus it is losing the heat. The ice is gaining heat.

McdeltaT

Mice*Cice(10) * MiceLf + MiceCw(25)= MiceCw(25-11) + MalCal(25-11)

I think I'm on the right track, but after I plug in the values that I know and I solve for the mass of ice, I'm getting a very large number which means I'm making a mistake somewhere. Any suggestions?