Answer:
t = 17658 s = 294.3 min = 4.9 h
Explanation:
The general formula for power is:

where,
P = Power of the Motor = 50 KW = 50000 W
W = Work Done by Motor = Change in P.E of Water = mgh
g = acceleration due to gravity = 9.81 m/s²
m = mass of water = ρV
h = depth of water = 180 m
ρ = density of water = 1000 kg/m³
V = Volume of Water = 500 m³
t = time taken = ?
Therefore,

<u>t = 17658 s = 294.3 min = 4.9 h</u>
<span>b. weakens as 1/d, where d is the distance between objects.</span>
Answer:
The distance traveled during its acceleration, d = 214.38 m
Explanation:
Given,
The object's acceleration, a = -6.8 m/s²
The initial speed of the object, u = 54 m/s
The final speed of the object, v = 0
The acceleration of the object is given by the formula,
a = (v - u) / t m/s²
∴ t = (v - u) / a
= (0 - 54) / (-6.8)
= 7.94 s
The average velocity of the object,
V = (54 + 0)/2
= 27 m/s
The displacement of the object,
d = V x t meter
= 27 x 7.94
= 214.38 m
Hence, the distance the object traveled during that acceleration is, a = 214.38 m
The gravitational force between them is <em>1.25 x 10^20 Newtons.</em>
(I think you must have typed the mass of the moon wrong.
It must be 6.0 x 10^22 kg.)