JEE Main 2020PhysicsGravitationEscape Speed And Motion Of SatellitesmediumNumerical

JEE Main 2020Gravitation Question with Solution

From: JEE Main 2020 (Online) 8th January Evening Slot

Question

An asteroid is moving directly towards the centre of the earth. When at a distance of 10R (R is the radius of the earth) from the earths centre, it has a speed of 12 km/s. Neglecting the effect of earths atmosphere, what will be the speed of the asteroid when it hits the surface of the earth (escape velocity from the earth is 11.2 km/s) ? Give your answer to the nearest integer in kilometer/s _____.

Enter your answer

Show full solutionCorrect answer: 16
Correct answer
16

Step-by-step explanation

U1 + K1 = U2 + K2

=



....(1)

Given escape velocity Ve = 11.2 km/s

= 11.2



So from (1)



= + 112.896

V2 = 16 km/s

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About this question

This is a previous-year question from JEE Main 2020, covering the Gravitation chapter of Physics. PrepSharp catalogues every PYQ from JEE Main with a verified answer key and step-by-step solution prepared by IIT alumni — so you can search by chapter, topic or year and revise efficiently.