Usually in joules. In physics, the unit for energy is joules.
Answer:
3.36m or 1680 N
Explanation:
Given:
Mass of the satellite =m
Mass of the moon Ganymede, M = 1.48 × 10²³ kg
Radius of Ganymede, R = 2631 km
Distance of satellite above the surface of the moon, d = 300 km
According to Universal Gravitational law:
where, G is the gravitational constant, M and m are mass of the objects and (R+d) is the distance between the centers of the objects.
Substitute the values:
If we consider mass of a satellite to be about 500 kg, the gravitational force between the moon and the satellite would be:
V₀ = V₁ + 2ax
V₀ = final velocity which is 0 m/s
V₁ = initial velocity which is 20 m/s
x = distance which is 60-(0.5 x 20) =50m
this is because his reaction time is 0.5 sec so he traveled 10m before stepping on the break paddle.
a= (V₀-V₁) / 2x
= (0-20) / 2*50
= -0.2m/s
the negative is because it is a deceleration speed hence it is 0.2m/s
From the formula
F = kx
F = k × 0.16
We know that F = mg = m×9.8
Therefore; kx = mg
Thus, k/m = g/x
Hence, k/m = 9.8/ 0.16 = 61.25
But; ω = √(k/m) = 2πf = 2π/t
√(k/m) = 7.8262
Thus, T= 2π/ 7.8262
= 0.8024 seconds