Q. The value of $'g'$ at a particular point is $9.8\ m/s^{2}$. Suppose the earth suddenly shrinks uniformly to half its present size without losing any mass. The value of $'g'$ at the same point (assuming that the distance of the point from the centre of earth does not shrink) will now be
A) $4.9\ m/s{ec}^{2}$
B) $3.1\ m/s{ec}^{2}$
C) $9.8\ m/s{ec}^{2}$
D) $19.6\ m/s{ec}^{2}$
Explanation
(c) $g = \frac{GM}{r^{2}}$. Since $M$ and $r$ are constant, so $g = 9.8m/s^{2}$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.