CE level Phy Heat Qu.

(2) Internal energy means the total amount of kinetic energy and potential energy . Heat is used to increase the kinetic energy and potential energy of the molecules , so it is true .

(3) The two objects may have different specific heat capacity , so the rate of temperature may rise in different rate . so it is wrong .

Since the heater power and time of heating are the same, the amount of energy given to both objects (equal to power x time) should be the same (assuming no heat loss to the surroundings).

(1) and (2) refer to the same:
Heat means the work done by the heater on the object in form of internal energy.

唔係PAST PAPER 黎

係KEN CHAN D EX.

2008-04-14 23:44:19 補充：
我都係咁諗...

但佢有幾條都一樣問法

個答案都係咁

希望有高手可以解答下

想問你lee題係邊年ka? 我都覺得(2)有d問題。

2008-04-14 23:43:03 補充：
oh, 咁可能答案有錯啦!
internal energy = PE + KE
既然(3)係錯嘅, 即係two objects may have different rise in temperature, 咁KE gain 都未必唔同啦 ; 就算佢地轉緊state, 咁PE gain都可以唔同, 正如你所講[可能唔同MASS ],
於是gain in internal energy應該都未必同。個人意見, 答案只有(1)。

2008-04-15 00:43:05 補充：
明白了, 多謝大哥^^