Answer : The time required is, 16.1 minutes.
Explanation :
First we have to calculate the amount of heat required to increase the temperature is:


where,
Q = amount of heat required = ?
m = mass
= density of air = 
V = volume of air
C = specific heat of air = 
= change in temperature = 
Now put all the given values in above formula, we get:



Now we have to calculate the time required.
Formula used :

where,
t = time required = ?
Q = amount of heat required = 
P = power = 1500 W
Now put all the given values in above formula, we get:


Thus, the time required is, 16.1 minutes.
Answer:
the mass of the air in the classroom = 2322 kg
Explanation:
given:
A classroom is about 3 meters high, 20 meters wide and 30 meters long.
If the density of air is 1.29 kg/m3
find:
what is the mass of the air in the classroom?
density = mass / volume
where mass (m) = 1.29 kg/m³
volume = 3m x 20m x 30m = 1800 m³
plugin values into the formula
1.29 kg/m³ = <u> mass </u>
1800 m³
mass = 1.29 kg/m³ ( 1800 m³ )
mass = 2322 kg
therefore,
the mass of the air in the classroom = 2322 kg
Kinetic energy is movement, thus movement would be a characteristic that allows an object to have kinetic energy