Question

If two balls of some mass are dropped from the same height, would they fall down at the same time?

Answer 1

when no resistive forces are present then both the balls will reach the ground simultaneously. This is because acceleration due to gravity is independent of mass of the falling object. i.e.$g=GM/R²$ where $G=6.67\times 10²³Nm²/kg²,$ M = mass of earth and R is radius of earth.Let us assume that both are metallic balls. In such case, we have to take into account the magnetic field of earth (which will give rise to eddy currents, and these eddy currents will be more, if surface area will be more) and viscous drag of air ( viscous drag is proportional to radius of falling ball), then bigger ball will take slightly more time than the smaller ball.