Answer:
2.9 kg
Explanation:
Given that a 0.775-m3 rigid tank initially contains air whose density is 1.18 kg/m3.
According to the definition of density
Density = mass/volume
1.18 = mass / 0.775
Mass = 1.18 × 0.775
Mass = 0.9145 kg
Given that the tank is connected to a high-pressure supply line through a valve. The valve is opened, and air is allowed to enter the tank until the density in the tank rises to 4.95 kg/m3.
Using the same density formula
Density = mass/volume
4.95 = mass / 0.775
mass = 3.83625 kg
To determine the mass of air that has entered the tank, take away the mass of the air initial in the tank from the mass calculated
Mass = 3.83625 - 0.9145
Mass = 2.923kg
Therefore, the mass of air that has entered the tank is 2.9 kg approximately.
