Tugas 1 heat energy

Subject                                   : Physics

Class/Smt                               : VII/2

Academic Year                       : 2012-2013

Standard Competence          : Heat Energy

1. What is the amount of energy required to rises the temperature of 3kg of Brass from 20^oC to 100^oC, given that the specific heat capacity of brass is 380 J/Kg^oC?
2. We mix 50grams water at 10⁰C and 100grams water at 75⁰C. What is the mixture temperature, if the specific heat of water is 4200 J/Kg⁰C?
3. Mr. Hari cooks 10gr water with 1000J and the initial temperature is 30⁰C. What is the final temperature if the specific heat of water is 4200 J/Kg⁰C?
4. How much energy is needed to change 1Kg water at -5⁰C  to 100^oC?given the specific heat capacity of ice=2100 J kg^oC and specific heat capacity of water = 4200 J kg^o C and the melting heat is 360000 J/Kg?