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JEE Main20254 Apr 2025Evening ShiftPhysicsGravitationActual

An object is kept at rest at a distance of 3 R above the earth's surface where R is earth's radius. The minimum speed with which it must be projected so that it does not return to earth is : (Assume M = mass of earth, G = Universal gravitational constant)

Options

  1. AGM 2 R
  2. BGM R
  3. C3 GM R
  4. D2 GM R

Correct answer

A. GM 2 R

Step-by-step solution

aligned & P _ P + k _ P = P _ o + k ₀ & - GMm 4 R + 1 2 mV _ P ^2=0 & ~V _ P = GM 2 R aligned Choice 1

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