The mass of a planet and its diameter are three times those of earth's. Then the  acceleration due to gravity on the surface of the planet is ....... $m/s^2$

A body weighs $63\; N$ on the surface of the earth. What is the gravitational force (in $N$) on it due to the earth at a height equal to half the radius of the earth ?

If the radius of the earth be increased by a factor of $5,$ by what factor its density be changed to keep the value of $g$ the same ?

At what depth below the surface of the earth, acceleration due to gravity $g$ will be half its value $1600 \,km$ above the surface of the earth

Given below are two statements: One is labelled as Assertion $A$ and the other is labelled as Reason $R$.

Assertion $A$: If we move from poles to equator, the direction of acceleration due to gravity of earth always points towards the center of earth without any variation in its magnitude.

Reason $R $: At equator, the direction of acceleration due to the gravity is towards the center of earth. In the light of above statements, choose the correct answer from the options given below

A spherical planet has a mass $M$ and diameter $D$ . A particle of mass $m$ falling freely near the surface of this planet will experience an acceleration due to gravity , equal to