Question

A 10.g cube of copper at a temperature T1 is placed in an insulated cup containing 10.g of water at a temperature T2. If T1>T2, which of the following is true of the system when it has attained thermal equillibrium? (The specific heat of copper is 0.385 J/g degrees C) and the specific heat of water is 4.184 J/g degrees C)

A. The temperature of the copper changed more than the temperature of the water.

B. The temperature of the water changed more than the temperature of the copper.

C. The temperature of the water and the copper changed by the same amount.

D. The relative temperature changes of the copper and the water cannot be determined without knowing T1 and T2.

Pick the correct answer choice and explain why it is true.

Answer 1

answer :

D. The relative temperature changes of the copper and the water cannot be determined without knowing T1 and T2.

explanation :

change in temperature of Cu = T1 -T

change in temperature of water = T -T2

q = m Cp dT

T = equilibrium Temperature

heat loss copper loss = heat gain by water

10 x 0.385 x (T1-T) = 10 x 4.184 x (T-T2)

0.385 x (T1-T) = 4.184 x (T-T2) ------------------------>

if T1 , T2 are know we can estimate temperature changes otherwise we cannot conclude which has higher change