Energy required to heat different materials?

AI Thread Summary
The discussion centers on understanding how to calculate the energy required to change the temperature of materials using the specific heat capacity formula Q=mcΔT. The specific heat capacity 'c' indicates the energy needed to raise the temperature of a unit mass by 1°C, with units typically in J/(g°C) or J/(kg°C). In the example provided, a 10kg block of marble with a specific heat capacity of 600 requires 6,000 joules to increase its temperature by 1°C. The calculation for decreasing the temperature is similar, using the same formula with a negative change in temperature. Overall, the energy calculated using this formula will always be in joules.
J-Girl
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Hello:) I am doing thermal physics at the moment, and am up to the part on specific heat capacity. I know that the equation Q=mc\DeltaT refers to the amount of energy required to raise the temperature by 1 degree celcius, but I am just a bit confused about how the energy is calculated. For example, if i have a 10kg block of marble with specific heat capacity of 600, and i want to know how much energy is required to increase the temperature by 1 degree celcius, and i do: Q=(10)(600)(1), and my final answer is 6,000, is it in joules, because its energy? Also, if i want to know how much energy is required to DECREASE the temperature by 1 degree celcius, do i do Q=(10)(600)(-1)?
thanks:):)
 
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Hi J-Girl,

The specific heat capacity 'c' is defined as the energy needed to heat 1 g (or maybe 1 kg) of material by 1°C. As a result, it has dimensions of energy per unit mass and per unit temperature. This corresponds to units of J/(g°C) or J/(kg°C). You need to find out which of these two options are the units your stated c value of "600" is in.

But, you can see that with these units, everything will work out as needed -- from the equation, Q will turn out to be in joules.
 
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