Question

A jeweler is heating a gold bar. It takes 7 joules of heat to raise the temperature of the bar 1°C. The initial temperature of the bar is 25°C. How many joules of heat would be required to raise the temperature of the gold bar to 26°C, 27°C, 28°C, 29°C, 30°C, and 35°C?

Answer 1

We are given that it takes 7 joules of heat to raise the temperature of the bar by 1°C. Therefore this means that the heating capacity Cp is:

Cp = 7 J / °C

 

The formula for the amount of heat required is:

heat = Cp (Tf – Ti)

where Ti is initial temperature = 25°C, and Tf is the final temperature

 

When Tf = 26°C

heat = 7 (26 – 25) = 7 J

 

When Tf = 27°C

heat = 7 (27 – 25) = 14 J

 

When Tf = 28°C

heat = 7 (28 – 25) = 21 J

 

When Tf = 29°C

heat = 7 (29 – 25) = 28 J

 

When Tf = 30°C

heat = 7 (30 – 25) = 35 J

 

When Tf = 35°C

heat = 7 (35 – 25) = 70 J