Confusing Phase Change Question

[deleted92121]

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Lead bullet with mass of 0.003 kg with initial temp of 30 C is fired with initial velocity of 240 m/s into large block of ice that is initially at 0 C. If bullet becomes embedded in ice, what is mass of ice that melted?

I set it up as Q gained = Q lost but am not getting the right answer at all. Do I need to do something with the initial velocity? This one is tripping me up something awful.

 

[circulus vitios]

Are you accounting for the bullet's initial thermal and kinetic energy?

 

[image187]

yeah, I think however you set up your equation you should try to figure out exactly what
energy the bullet has at the moment it hits the Ice (thermal, kinetic...)

 

[deleted92121]

That makes sense. Perhaps using KE = 1/2 mv^2.

So would KE be gained or lost though? I would put it on the gained side as the ice gained the energy from the bullet.