Escape Velocity

IMPORTANT

Escape Velocity: Overview

This topic covers concepts such as Escape Velocity of Bodies and Reason for No Atmosphere on The Moon.

Important Questions on Escape Velocity

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Two planets A and B have the same material density. If the radius of A is twice that of B, then the ratio of the escape velocity   V A V B is

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A missile is launched with a velocity less than the escape velocity. The sum of kinetic energy and potential energy is :

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The escape velocity on the surface of the moon is small because moon has a less surface _____.
 

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The escape velocity on the moon is less than that on the earth.

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There's no atmosphere on the moon. Why?

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Two bodies each of mass M are kept fixed with a separation 2L. A particle of mass m is projected from the mid-point of the line joining their centres perpendicular to the line. The gravitational constant is G. The correct statement s is (are)

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The escape velocity of a spherical planet of radius R and density ρ is V. If the radius of this planet is changed to 3R and density is changed to 3ρ, then the escape velocity of the planet will be changed to

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Compare the escape velocities of earth and moon.

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What is the reason behind the moon having no atmosphere?

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Velocity of escape, from earth’s surface, is _____  km s-1.

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Calculate the escape velocity of a body from the surface of the earth. (Given: G=6.67 x 10-11 Nm2/kg2, R=6400 km, g=9.8 m/s2)

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Define escape velocity. Write an expression for the escape velocity of an object from the surface of the earth.

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If any object is thrown upwards with a velocity more than 11.2 km/sec, then the object will:

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Gravitational acceleration on the surface of the planet is 611g, where g is the acceleration due to gravity on the surface of earth. The average mass density of the planet is 23 times that of the earth. If the escape speed on the surface of the earth is taken to be 11 km s-1, then find the escape speed on the surface of the planet (in km s-1).

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Velocity of escape is _____ times the orbital velocity of a satellite revolving very close to the surface of earth. 
(Choose from 3 (1.732) or 2 (1.414).)

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Choose the incorrect statements from the following options.

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A satellite is revolving at a height h from the surface of earth. Then the change in velocity for the satellite to escape the gravitational field of earth, is:

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There are two identical starts of mass 3×1031 kg each with distance  2×1011m between them. Now a material is projected with velocity v from the midpoint of the line joining the stars. What should be the minimum value of v so that it goes out by gravitational field of the given stars?

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The ratio of accelerations due to gravity g1 : g2 on the surfaces of two planets is 5 :2 and the ratio of their respective average densities ρ1:ρ2 is 2 :1 . What is the ratio of respective escape velocities v1 :v2  from the surface of the planets?

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The escapse velocity from the Earth is 11 kms-1. The escpe velocity from a planet having twice the radius and same mean density as that of Earth is