Students to classrom heat transfer

AI Thread Summary
A student calculates that 90 students produce a total heat transfer of 27 million joules over 50 minutes. The classroom's volume is 3200 cubic meters, with air having a thermal capacity of 1020 J/kgK and a density of 1.20 kg/m3. The student seeks assistance in determining the increase in air temperature given that no heat escapes the room. They confirm the calculation of total heat transferred but require guidance on the formula to relate heat input to temperature change. Understanding this relationship is crucial for solving the problem effectively.
snabelpablo
Messages
7
Reaction score
0
A student produces heat with a rate of 100W. How much heat is transferred from 90 students to a classroom in 50 minutes?

Attempt at solution:
100W (100 J/s) * 90 students * 3000 seconds = 2,7 * 10^7 J. Does this make sense?

The classroom is 3200 cubic meters and the air in it has a thermal capacity of 1020 J/kgK and a density of 1.20 kg/m3. If no heat escapes from the room and the ventilation is broken, how much does the air temperature increase during the 50 minutes?

Attempt at solution:
None. Some help, please?
 
Physics news on Phys.org
The number of Joules transferred is correct. Do you know of an expression that relates the change in temperature to the heat input?
 

Thread 'Errors and significant figures'

I multiplied the values first without the error limit. Got 19.38. rounded it off to 2 significant figures since the given data has 2 significant figures. So = 19. For error I used the above formula. It comes out about 1.48. Now my question is. Should I write the answer as 19±1.5 (rounding 1.48 to 2 significant figures) OR should I write it as 19±1. So in short, should the error have same number of significant figures as the mean value or should it have the same number of decimal places as...
View full post »
Thread 'A cylinder connected to a hanging mass'

Thread 'A cylinder connected to a hanging mass'

Let's declare that for the cylinder, mass = M = 10 kg Radius = R = 4 m For the wall and the floor, Friction coeff = ##\mu## = 0.5 For the hanging mass, mass = m = 11 kg First, we divide the force according to their respective plane (x and y thing, correct me if I'm wrong) and according to which, cylinder or the hanging mass, they're working on. Force on the hanging mass $$mg - T = ma$$ Force(Cylinder) on y $$N_f + f_w - Mg = 0$$ Force(Cylinder) on x $$T + f_f - N_w = Ma$$ There's also...
View full post »

Similar threads

Thermodynamics relating to temperature and phase changes
Replies
1
Views
1K
Heat Transfer: Effect of a Heat Fin
Replies
4
Views
2K
Heat transfer to solution per litre
Replies
2
Views
1K
Calculating Heat Transfer in a Cylinder with CO2 Gas at Different Temperatures
Replies
3
Views
1K
Calculating Heat Transfer in a Water Bath with a Changing Volume and Temperature
Replies
6
Views
2K
Heat Question -- Temperature rise of a hiker on a long hike
Replies
1
Views
2K
Thermodynamics relating to temperature and phase changes V.2
Replies
1
Views
1K
White Roof Vs. Black Roof on a house
Replies
1
Views
1K
How much water evaporates per minute from a copper pot on a stove?
Replies
4
Views
1K
Determine the thermal effieincy of a heat transfer process
Replies
4
Views
2K

Hot Threads

Recent Insights

Back
Top