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2 years ago

7

Two objects are placed in thermal contact and are allowed to come to equilibrium in isolation. The heat capacity of Object A is

three times the heat capacity of Object B and the initial temperature of Object A (TA) is twice the initial temperature of Object B (TB).
1)

What will the final temperature of the two-object system be?

2TB

1.75TB

1.5TB

1.2TB

TB

1 answer:

Oksi-84 [34.3K]2 years ago

8 0

Answer:

Explanation:

Heat capacity A = 3 x heat capacity of B

initial temperature of A = 2 x initial temperature of B

TA = 2 TB

Let T be the final temperature of the system

Heat lost by A is equal to the heat gained by B

mass of A x specific heat of A x (TA - T) = mass of B x specific heat of B x ( T - TB)

heat capacity of A x ( TA - T) = heat capacity of B x ( T - TB)

3 x heat capacity of B x ( TA - T) = heat capacity of B x ( T - TB)

3 TA - 3 T = T - TB

6 TB + TB = 4 T

T = 1.75 TB

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