## Question

### Solution

Correct option is

128 N, 80 kg, , 12 m (approx).

The weight (W) of the person on the earth is 80 kg-wt. Hence the mass (m) is 80 kg. If M be the mass and R the radius of the moon, then the force of attraction exerted by the moon on the person is

This is the weight W’ (say) of the person on the moon.

The mass (m) of the person on the moon will be 80 kg (as on the earth). Hence for the person standing on the moon the acceleration due to gravity due to the attraction of the moon will be

For the person standing on the earth the acceleration due to gravity due the earth is 9.8 N kg –1. Therefore, for a person standing on the moon the acceleration due to gravity as compared to that on the earth will be  So the person can jump 6 times higher on the moon. Hence height of the jump on the moon = 6 × 2 = 12 m (approx).

In moving on a plane, g does not affect. Hence the person will walk on the moon also 100 m in 1 minute.

#### SIMILAR QUESTIONS

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The distance of two planets the sun are 1013 and 1012 meter respectively. Find the ratio of time-periods and speeds of the two planets.

Q2

Two masses, 800 kg and 600 kg, are at a distance 0.25 m apart. Compute the magnitude of the intensity of the gravitational field at a point distant 0.20 m from the 800 kg mass and 0.15 m from the 600 kg mass (G = 6.66× 10 –11 N m2 kg–2).

Q3

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Q4

What will be the acceleration due to gravity on the surface of the moon if its radius is 1/4th the radius of the earth and its mass is (1/80)th the mass of the earth.

Q5

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Q6

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Q7

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Q8

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Q10

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