Physics heat problem Using calories.

AI Thread Summary
To calculate the calories needed to raise the temperature of a 44 g gold chain from 20°C to 125°C, it's essential to use the specific heat capacity of gold in the calculation. Simply multiplying the mass by the temperature change is insufficient, as it does not account for the material's thermal properties. The correct approach involves multiplying the mass by the temperature change and the specific heat capacity of gold. Additionally, if the energy is calculated in Joules, it must be converted to Calories for the final answer. The accurate calculation yields the correct number of calories required for the temperature increase.
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Homework Statement



How many calories will it take to raise the temperature of a 44 g gold chain from 20°C to 125°C?


Homework Equations



You are trying to raise the temperature of 44 g. of gold by 105 degrees celsius. I tried 44 x 105 but this answer was incorrect.

3. The Attempt at a Solution
The answer is got was 4620 cal. But this was not correct.
 
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You also have to multiply by the heat capacity of gold(solid) to get the number of calories.

Chet
 
They told you it was gold because different materials have different thermal properties. It takes more energy to heat up 44g of water by 105C then it does to do the same if it's gold, wood, air...

See the table of data for various materials down here..
http://en.wikipedia.org/wiki/Heat_capacity#Table_of_specific_heat_capacities

Note the units. If you use this data you will have to convert the resulting energy from Joules to Calories.
 
Thank you very much! I came up with the correct answer
 
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