The time period of revolution of moon around the earth is 28 days and radius of its orbit is 4 × 10 5 km. If G = 6.67 × 10 –11 Nm 2 /kg 2 then find the mass of the earth.

Given in the question that, The time period of revolution of moon around the earth is, T = 28 × 24 × 60 × 60 s And the radius of its orbit is, a = 4 × 10 5 × 1000 m And the gravitational constant is, G = 6 · 67 × 10 - 11 Nm 2 / kg 2 Now, from Kepler's law, T 2 = 4 π 2 G M a 3 ⇒ M = 4 π 2 a 3 G T 2 ⇒ M = 4 × 3 · 14 × 3 · 14 × 4 × 10 8 3 6 · 67 × 10 - 11 × 28 × 24 × 3600 2 ⇒ M = 6 · 47 × 10 24 kg Hence, the mass of earth is 6 · 67 × 10 24 kg .

The time period of revolution of moon around the earth is 28 days and radius of its orbit is 4 × 10 5 km. If G = 6.67 × 10 –11 Nm 2 /kg 2 then find the mass of the earth.

Given in the question that, The time period of revolution of moon around the earth is, T = 28 × 24 × 60 × 60 s And the radius of its orbit is, a = 4 × 10 5 × 1000 m And the gravitational constant is, G = 6 · 67 × 10 - 11 Nm 2 / kg 2 Now, from Kepler's law, T 2 = 4 π 2 G M a 3 ⇒ M = 4 π 2 a 3 G T 2 ⇒ M = 4 × 3 · 14 × 3 · 14 × 4 × 10 8 3 6 · 67 × 10 - 11 × 28 × 24 × 3600 2 ⇒ M = 6 · 47 × 10 24 kg Hence, the mass of earth is 6 · 67 × 10 24 kg .

force of attraction exerted by the earth.

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Beta Question Bank for Medical: Physics>Chapter 11 - Gravitation>BEGINNER'S BOX - 4>Q 5

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The time period of revolution of moon around the earth is 28 days and radius of its orbit is 4 × 10⁵ km.
If G = 6.67 × 10^–11 Nm²/kg² then find the mass of the earth.

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Beta Question Bank for Medical: Physics>Chapter 11 - Gravitation>BEGINNER'S BOX - 4>Q 6

Let the speed of the planet at the perihelion P in Fig. be v_P and the Sun-planet distance SP be r_p. Relate (r_p, v_P) to the corresponding quantities at the aphelion (r_A, v_A). Will the planet take equal times to traverse BAC and CPB ?
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Beta Question Bank for Medical: Physics>Chapter 11 - Gravitation>BEGINNER'S BOX - 4>Q 7

A comet orbits the sun in a highly elliptical orbit. Does the comet have a constant linear speed, angular speed, angular momentum, kinetic energy, potential energy, total energy throughout its orbit? Neglect any mass loss of the comet when it comes very close to the Sun.

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Beta Question Bank for Medical: Physics>Chapter 11 - Gravitation>BEGINNER'S BOX - 4>Q 8

Asatellite moves in a circular orbit around the earth. The radius of this orbit is one half that of the moon’s orbit. Find the time in which the satellite completes one revolution.

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Beta Question Bank for Medical: Physics>Chapter 11 - Gravitation>BEGINNER'S BOX - 4>Q 9

A small satellite revolves round a planet in an orbit just above planet’s surface. Taking the mean density of planet as