Passengers in an aircraft are subject to the Normal and Gravity Force acting on them at a low 'orbit', so tiny that it can be many times compared to the same surface of the earth when speaking in general terms.
In a high orbit space vehicle or in the same space, said force decreases considerably or simply disappears, generating the sensation of weightlessness.
Remember that the Force of Gravity is given under the principle

Where,
G = Gravitational Universal constant
M = Mass of the planet
m = mass of the object
r = Distance from center of the planet
When the radius grows considerably the gravitational force begins to decrease.
The work done is equal to the change in potential energy which is:
P.E = mgh
P.E = 500 x 9.81 x 15
P.E = 73,575 J
Power = work / time
Power = 73,575 / 20
Power = 3,700 Watts
Answer:

Explanation:
Let at any moment of time the friend's car is at some horizontal distance "x" from the position of balloon.
Now if the altitude of the balloon is fixed and it is at height "h"
so here we will have

now we know that
initially the angle of the friend's car is 35 degree
so the horizontal distance will be

similarly if the angle after passing the car position is 36 degree
then we have

now the speed of the balloon is constant
so we have




so the final position of friend when the angle is 36 degree


Explanation:
It is given that,
Current in wire 1, I₁ = 10 A
Current in wire 2, I₂ = 20 A
Distance between wires, d = 10 cm = 0.1 m
Force per unit length is given by :




So, the magnetic force acting per unit length of the wires
. Since, the current is in same direction. So, the force is attractive in nature.