The formula for the work done in emptying a tank is this:
W = ĻyV
where
Ļ is the specific weight
y is the center of gravity
V is the volume of the liquid
The specific weight can be calculated using the formula
Ļ = Ļg
where
Ļ is the density
g is the acceleration due to gravity
Solving for Ļ
Ļ = 817.15 kg/m3 (9.81 m/s2)
Ļ = 8016.24 N/m3
The center of gravity of a completely filled cylindrical tank is just 1/2 of the height. So,
y = 3 cm
The volume of the kerosene is just the volume of tank. Using the formula for the volume of a cylinder
V = ĻrĀ²h
V = Ļ (3Ā²) (6)
V = 54Ļ mĀ³
Therefore, the word done is
W = 8016.24 (6) (54Ļ)
W = 8159538.47 J or
W = 8.16 MJ
