A particle of mass ‘m’ is kept at rest at a height 3R from the surface of earth

⇦

⇨

A particle of mass ‘m’ is kept at rest at a height 3R from the surface of earth, where ‘R’ is radius of earth and ‘M’ is mass of earth. The minimum speed with which it should be projected, so that it does not return back, is( g is acceleration due to gravity on the surface of earth)

Options

(a) (GM / R)¹/²
(b) (GM / 2R)¹/²
(c) (GR / 4)¹/²
(d) (2G / 4)¹/²

Correct Answer:

(GM / 2R)¹/²

Explanation:

As we know, the minimum speed with which a body is projected so that it doe snot return back is called escape speed.
vₑ = √(2GM / r) = √(2GM / R + h) = √(2GM / 4R)
= (GM / 2R)¹/² ( h = 3R)

Related Questions:

1. A person can see clearly objects only when they lie between 50 cm and 400 cm from
2. A solenoid of length l metre has self inductance L henry. If number of turns
3. A radioactive substance contains 10000 nuclei and its halflife period is 20 days
4. A short bar magnet of magnetic moment 0.4 JT⁻¹ is placed in a uniform magnetic field
5. A particle is executing SHM along a straight line. Its velocities at distances

Topics: Gravitation (63)
Subject: Physics (2479)

---

Important MCQs Based on Medical Entrance Examinations To Improve Your NEET Score

18000+ students are using NEETLab to improve their score. What about you?

Solve Previous Year MCQs, Mock Tests, Topicwise Practice Tests, Identify Weak Topics, Formula Flash cards and much more is available in NEETLab Android App to improve your NEET score.

---

Share this page with your friends