Question

It is known that falling apple is attracted towards the Earth. We all know that the apple will also exert an equal and opposite force on the Earth. If so, we don’t observe Earth moving towards the apple, why?

• A. Both are applying equal and opposite force on each other so it gets cancelled out.
• B. The acceleration produced by the fruit in Earth would be negligible.
• C. The acceleration produced in the fruit in Earth would be very high.
• D. No acceleration produced by the fruit in Earth.

Answer 1

The correct option is B

The acceleration produced by the fruit in Earth would be negligible.

From Newton’s $2^{nd}$ law, we know that acceleration is inversely proportional to mass.
$F=ma$
Acceleration = $\frac{F}{m}$
The mass of apple is negligibly small as compared to that of the Earth. So, for same gravitational force, acceleration of the Earth is very small. Thus, Earth will not move, whereas the apple will have considerable acceleration (less mass), which brings it down.