For this case, the first thing you should know is that density is defined as the quotient between mass and volume.
d = m / v
We have then for this case that the density is:
d = 103 Kg / m ^ 3
The volume is given by:
V = A * d
Where
A: area of the city
d: height of the rain
Also, for calculation purposes, you must know the following measure:
1Km = 1000m
1 inch = 0.0254 meters
Calculating the volume we have:
V = (22 * (1000/1) ^ 2) * (2 * (0.0254 / 1)) = 1117600 m ^ 3
Then, calculating the mass we have:
m = d * v
m = (103) * (1117600) = 115112800 Kg
Equivalently
m = 1.15 * 10 ^ 8 Kg
answer
mass of water fell on the town was 1.15 * 10 ^ 8 Kg
Answer:
B. -40 kgm/s is the answer
Answer
given.
Mass of big fish = 15 Kg
speed of big fish = 1.10 m/s
mass of the small fish = 4.50 Kg
speed of the fish after eating small fish =?
a) using conservation of momentum
m₁v₁ + m₂v₂ = (m₁+m₂) V
15 x 1.10 + 4.50 x 0 = (15 + 4.5)V
16.5 = 19.5 V
V = 0.846 m/s
b) Kinetic energy before collision


KE₁ = 9.075 J
Kinetic energy after collision

KE₂ = 6.98 J
Change in KE = 6.98 - 9.075 = -2.096 J
hence,
mechanical energy was dissipated during this meal = -2.096 J