Question

The gravitational potential energy of a rocket of mass 200 kg at a distance 10⁶ m from the centre of the earth is 3 × 10⁸ J. The weight of the rocket at a distance 10⁸ m from the centre of the earth is ______.

विकल्प

• 6 × 10^-2 N

• 3 × 10^-2 N

• 1.5 × 10^-2 N

• 4.5 × 10^-2 N

Answer 1

The gravitational potential energy of a rocket of mass 200 kg at a distance 10⁶ m from the centre of the earth is 3 × 10⁸ J. The weight of the rocket at a distance 10⁸ m from the centre of the earth is 3 × 10^-2 N.

Explanation:

m = 200 kg

r₁ = 10⁶ m

PE `="GMm"/r_1=3xx10^8  "J"`

∴ GMm = 3 × 10⁸ × 10⁶

Wt = mg `="GMm"/(10^8)^2=(3xx10^8xx10^6)/(10^8xx10^8)=0.03  N=3xx10^-2  N`