Question

A 0.1 kg block of brass is cooled until it releases 56.4 J of heat. If the temperature of the block was 5 K initially, what is it now?

Answer 1

Answer:

3.5 K

Explanation:

When a sample of a substance releases heat energy, its temperature decreases according to the equation:

$Q=mC(T_f-T_i)$

where

Q is the heat energy released

m is the mass of the substance

C is the specific heat capacity

$T_i$ is the initial temperature

$T_f$ is the final temperature

For the block of brass in this problem, we have:

m = 0.1 kg is the mass

Q = -56.4 J is the heat energy released (negative since it is released)

C = 380 J/kg K is the specific heat capacity of brass

$T_i=5 K$ is the initial temperature

Solving for $T_f$, we find the final temperature:

$T_f=T_i + \frac{Q}{mC}=5+\frac{-56.4}{(0.1)(380)}=3.5 K$