JEE PHYSICS MCQ: GRAVITATION

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To remove an object from earth's gravitational field the speed that is to be given to it on the surface of the earth is nearly equal to

11.25 \mathrm{~km} / \mathrm{s}

. However, when an object on the earth is to be removed from the solar system, gravitational influence of the sun is taken in account. To remove an object from the solar system, the speed that is given to it on earth's surface is nearly equal to

45 \mathrm{~km} / \mathrm{s}

. The mass of the sun is

\mathrm{k}_1

times the mass of the earth and the orbital radius of the earth is

\mathrm{k}_2

times its radius. Find the value of

\mathrm{k}_1 / \mathrm{k}_2

View answer and explanation

Correct option: A

Option A (15) is correct. The ratio k1/k2 is found by equating the kinetic and potential energies required to escape both Earth's and the Sun's gravitational fields.

More Questions from GRAVITATION

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The escape velocity for a body projected vertically upwards from the surface of the earth is

11.2\mathrm{\;\;km}{\mathrm{s}^{ - 1}}

. If the body is projected in a direction making an angle of

{45^0}

with the vertical, the escape velocity will be The escape velocity of a body projected from the surface of earth is

v_e

. If the body is projected at an angle

\theta

to the horizontal surface of earth, then the escape velocity would be If different planets have the same density but different radii, then the acceleration due to gravity on the surface of the planet is related to the radius (R) of the planet as Which of the following statement is absolutely correct about mass Statement I: An astronaut in a satellite feels weightlessness:

Statement II: As observed by another astronaut's in the same satellite, force of gravity and centrifugal force balance each other. An iron ball and a wooden ball of the same radius are released from a height 'h' in vacuum. The time taken by both of them to reach the ground is