Consider a classroom for 57 students and one instructor, each generating heat at a rate of 100 W. Lighting is provided by 18 fluorescent lightbulbs, 40 W each, and the ballasts consume an additional 10 percent. Determine the rate of internal heat generation in this classroom when it is fully occupied. The rate of internal heat generation in this classroom when it is fully occupied is W.

The answer is 6392 W

Explanation:

Solution

Given that:

The total number of students in the class room is = 57

There are 18 light fluorescent bulbs of 40 W

The heat generated by an individual is = 100 W

The ballasts consume an additional of 10% from the generated heat

The rate of internal heat generation in he classroom when it is completely filled up is the sum or addition of heated generated because of the ballasts, light bulbs and individuals or persons is denoted as follows:

Q total = Q people + Q lights W

Now,

The heat that is been generated by the students in the classroom when occupied completely is stated below:

Q people = (The number of person) * (Q each)

Thus,

56 * 100

= 5600 W

Secondly, the heat generated from the lights is the same as the electrical energy been used by the lights

So,

Q lights = (Total number of lights) * (Q elec)

18 * 40

= 720 W

Then

The heat used by the ballasts is at 10 % of the Q lights

Which is Q ballasts = 10/100 * 720

= 72 W

Now,

We sum up both the heat generated from the lights bulbs, by the students and from the ballasts.

Thus

The the total heat generated from the classroom is shown below:

Q total = Q people + Q lights

=5600 + 720 + 72

=6392 W

Therefore the total heat generated is 6392 W