Very Basic Physics that I'm struggling on

AI Thread Summary
The discussion revolves around a physics problem involving heat transfer between a heated brass mass and water. The rise in temperature of the water is calculated to be 60°C, with the heat energy gained by the water determined to be 50,400J. The temperature drop of the brass mass is incorrectly calculated as -681°C, indicating an error since it cannot drop below absolute zero. It is assumed that the heat lost by the brass equals the heat gained by the water. The final temperature of the brass mass is suggested to be the same as that of the water after the heat exchange.
aguycalledwil
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Very Basic Physics...that I'm struggling on...

Homework Statement


In an experiment to find the temperature of a Bunsen flame, a 0.2kg brass mass is heated in the flame. The hot mass is then placed in a beaker containing 0.2 kg of water. The temperature of the water rises from 20C to 80C.
a)what is the rise in temperature of the water?
b)what is the heat energy gained by the water?
c)assuming the temperature of the mass to be T, what is the fall in temperature of the mass?
d)what is the heat lost by the mass?
e)assuming that the heat lost by the mass is the same as the heat gained by the water, find the temperature, T.

Homework Equations


H=m*c*rise in temperature

The Attempt at a Solution


I think I have the first four. I did...
a) 80C-20C = 60C
b) H=0.2*4200*60 = 50400J
c) H/mc=change in temp. therefore, -50400/0.2*370=change in temp. therefore, the change in temp. is -681C
d) I just assumed that the the heat lost by the mass is the same as the heat gained by the water, which is 50400J.
e) This one has me completely stuck...
 
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aguycalledwil said:
In an experiment to find the temperature of a Bunsen flame, a 0.2kg brass mass is heated in the flame. The hot mass is then placed in a beaker containing 0.2 kg of water. The temperature of the water rises from 20C to 80C.
a)what is the rise in temperature of the water?
b)what is the heat energy gained by the water?
c)assuming the temperature of the mass to be T, what is the fall in temperature of the mass?
d)what is the heat lost by the mass?
e)assuming that the heat lost by the mass is the same as the heat gained by the water, find the temperature, T.

The Attempt at a Solution


I think I have the first four. I did...
a) 80C-20C = 60C
b) H=0.2*4200*60 = 50400J
c) H/mc=change in temp. therefore, -50400/0.2*370=change in temp. therefore, the change in temp. is -681C
d) I just assumed that the the heat lost by the mass is the same as the heat gained by the water, which is 50400J.
e) This one has me completely stuck...

you already computed the temperature loss of the brass. The brass ends up at the same temperature of the water after losing 681 degrees
 
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