JEE Main 2021 (Online) 24th February Evening Shift | Gravitation Question 143 | Physics

A body weights 49N on a spring balance at the north pole. What will be its weight recorded on the same weighing machine, if it is shifted to the equator?

[Use $$g = {{GM} \over {{R^2}}}$$ = 9.8 ms^$$-$$2 and radius of earth, R = 6400 km.]

49 N

49.83 N

48.83 N

49.17 N

JEE Main 2021 (Online) 24th February Morning Shift

MCQ (Single Correct Answer)

-1

Four identical particles of equal masses 1 kg made to move along the circumference of a circle of radius 1 m under the action of their own mutual gravitational attraction. The speed of each particle will be :

$$\sqrt {{G \over 2}(1 + 2\sqrt 2 )} $$

$$\sqrt {{G \over 2}(2\sqrt 2 - 1)} $$

$$\sqrt {G(1 + 2\sqrt 2 )} $$

$${1\over2}\sqrt {G(1 + 2\sqrt 2 )} $$

JEE Main 2021 (Online) 24th February Morning Shift

MCQ (Single Correct Answer)

-1

Consider two satellites S₁ and S₂ with periods of revolution 1 hr. and 8 hr. respectively revolving around a planet in circular orbits. The ratio of angular velocity of satellite S₁ to the angular velocity of satellite S₂ is :

1 : 4

8 : 1

2 : 1

1 : 8

JEE Main 2021 (Online) 24th February Morning Shift

MCQ (Single Correct Answer)

-1

Two stars of masses m and 2m at a distance d rotate about their common centre of mass in free space. The period of revolution is :

$${1 \over {2\pi }}\sqrt {{{{d^3}} \over {3Gm}}} $$

$$2\pi \sqrt {{{3Gm} \over {{d^3}}}} $$

$${1 \over {2\pi }}\sqrt {{{3Gm} \over {{d^3}}}} $$

$$2\pi \sqrt {{{{d^3}} \over {3Gm}}} $$