Heater causes room temp to rise

[Bradracer18]

Here's yet another problem causing me trouble. I just don't understand(yet again) how to begin the problem. A little nudge in the right direction would be very much appreciated!

If a heater supplies 1.8 x 10^6 J/h to a room 6.5m X 4.6m X 3.0m containing air at 20 deg C and 1atm, by how much will the temperature rise in one hour, assuming no heat losses to the outside.


I obviously already figured the volume to be V=89.7 m^3...but lost as what to do next.

Thanks a ton!

Brad

 

[illwerral]

You need the specific heat capacity of air, which is measured in joules per gram per kelvin. Find out how much that air weighs, and then you should be able to calculate what you want with the simple formula:

change in energy = (specific heat capacity)*(mass)*(change in temperature)

Watch your units!

 

[kyle8921]

,

It seems like you are on the right track with calculating the volume of the room. The next step in solving this problem would be to use the formula Q = mcΔT, where Q is the heat energy supplied by the heater, m is the mass of air in the room, c is the specific heat capacity of air, and ΔT is the change in temperature. You can calculate the mass of air in the room by using the density of air (1.2 kg/m^3) and the volume you already calculated. Then, you can plug in the values and solve for ΔT. I hope this helps and good luck with your problem!