- #1
leo9999
- 8
- 0
Earlier today I've attended a physics exam and there is a query I'm not sure about.
A metallic cube (specific heat capacity 30 cal/K*Kg ) falls from an height of 50 m on a non-conducting surface, and it stops. After the inelastic collision, what is the temperature of the cube?
a_ The temperature doesn't change because the surface is non-conducting.
b_ We cannot find the temperature because we don't know the cube mass.
c_ It raises ( +3°K).
d_ It decreases ( -5°K).
In my opinion the correct answer is B. In fact, potential energy has to be dissipated and since the surface is non-conducting, there won't be a heat flow from the cube to the surface. So all potential energy will be used to increase the cube internal energy, then the temperature has to raise.
Without the cube mass, we can't calculate how much the temperature increases, but it should increase.
Am I right?
Thank you and sorry for my english!
A metallic cube (specific heat capacity 30 cal/K*Kg ) falls from an height of 50 m on a non-conducting surface, and it stops. After the inelastic collision, what is the temperature of the cube?
a_ The temperature doesn't change because the surface is non-conducting.
b_ We cannot find the temperature because we don't know the cube mass.
c_ It raises ( +3°K).
d_ It decreases ( -5°K).
In my opinion the correct answer is B. In fact, potential energy has to be dissipated and since the surface is non-conducting, there won't be a heat flow from the cube to the surface. So all potential energy will be used to increase the cube internal energy, then the temperature has to raise.
Without the cube mass, we can't calculate how much the temperature increases, but it should increase.
Am I right?
Thank you and sorry for my english!