Question 120: Gravitation

Question

The weight of a body at the surface of earth is 18 N. The weight of the body at an altitude of 3200 km above the earth's surface is (given, radius of earth $$\mathrm{R_e=6400~km}$$) :

Accepted Answer

The weight of an object at a height h from the Earth's surface is given by:
$$W' = W \left(\frac{R}{{R + h}}\right)^2$$
where:
W' is the weight at height h,
W is the weight at the Earth's surface,
R is the radius of the Earth,
h is the height above the Earth's surface.
In this problem, the weight at the Earth's surface W is given as 18 N, the radius of the Earth R is given as 6400 km, and the height h is given as 3200 km. Substituting these values into the equation gives:
$$W' = 18 N \left(\frac{6400~km}{{6400~km + 3200~km}}\right)^2 = 18 N \left(\frac{2}{3}\right)^2 = 18 N \cdot \frac{4}{9} = 8 N$$
Therefore, the weight of the body at an altitude of 3200 km above the Earth's surface is 8 N.

Answer

9.8 N

Answer

4.9 N

Answer

19.6 N

Answer

8 N

Gravitation

The weight of a body at the surface of earth is 18 N. The weight of the body at an altitude of 3200 km above the earth's surface is (given, radius of earth $\mathrm{R_e=6400~km}$) :

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