Question

An apple falls from a tree because of gravitational attraction between the earth and apple. If is the magnitude of force exerted by the earth on the apple and f2 is the magnitude of force exerted by apple on earth, then (a) f, is very much greater than f2 (b) f2 is very much greater than f, (c) f, is only a little greater than f2 (d) f, and f2 are equal

Answer 1

D f1 and f2 are equal

Answer 2

The force of attraction f is equal to f₂ , option (d)

Explanation :

The gravitational force of attraction is given by

F = $\frac{GMm}{r^2}$

Let the mass of the earth = M

mass of apple = m

distance between them = r

Force exerted by earth on the apple,

f = $\frac{GMm}{r^2}$

similarly force exerted by apple on earth

f₂ = $\frac{GMm}{r^2}$

so we can see that f is equal to f₂ , option (d)