Calculating energy needed to melt aluminum cans?

  • Thread starter Thread starter MarianaMoon
  • Start date Start date
  • Tags Tags
    Aluminum Energy
Join the discussion
Registration is free. Start your own thread to ask a follow-up.
5 replies · 8K views
MarianaMoon
Messages
3
Reaction score
0

Homework Statement


You have collected exactly 1500 aluminum cans for recycling, each with a mass of 13.9 g. How much energy is needed to melt them if their initial temperature is 25.5◦C? Assume
the specific heat, the latent heat and the melting point of aluminum are 899 J/kg ·◦C, 3.97 ×10^5 J/kg and 660.4◦C, respectively.
Answer in units of J.

Homework Equations


I'm pretty sure that the equations used are Q=mcΔT, and after getting that, using the Q=mL formula..

The Attempt at a Solution


So, for the Q=mcΔT part, I put; Q= (13.9)(899 J/kg◦C)(634.9)+(13.9)(397000 J/kg) which is 1.34*10^7. I put it in my homework online and it said it was incorrect. I later did Q=(13.9)(899)(634.9) which was 7933773.89 and then put it into Q=ml.. 7933773.89=13.9(397000) and it calculated to be 7933773.89=5518300. Do I subtract, divide? I have a feeling I'm doing it wrong. I don't know what to do after this step, my teacher was explaining it at the end of class really fast and I didn't get to finish writing down the notes.
 
Physics news on Phys.org