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
Explanation:
There are 3.28 feet in a meter.
1100 ft/s × (1 m / 3.28 ft) ≈ 335 m/s
Round as needed.
Question one :sound Energy
Question two :light and thermal energy
I hope this helps you
A little bit I can do
Answer:
The focal length of the concave mirror is -15.5 cm
Explanation:
Given that,
Height of the object, h = 20 cm
Radius of curvature of the mirror, R = -31 cm (direction is opposite)
Object distance, u = -94 cm
We need to find the focal length of the mirror. The relation between the focal length and the radius of curvature of the mirror is as follows :
R = 2f
f is the focal length
f = -15.5 cm
So, the focal length of the concave mirror is -15.5 cm. Hence, this is the required solution.