A projectile is fired from the surface of the earth with a velocity of 5 ms^-1 and angle θ with the horizontal. Another projectile fired from another…

A projectile is fired from the surface of the earth with a velocity of $\displaystyle 5 \mathrm{~ms}^{-1}$ and angle $\displaystyle \theta$ with the horizontal. Another projectile fired from another planet with a velocity of $\displaystyle 3 \mathrm{~ms}^{-1}$ at the same angle follows a trajectory which is identical with the trajectory of the projectile fired from the earth. The value of the acceleration due to gravity on the planet is (in $\displaystyle \mathrm{ms}^{-2}$) is : (given $\displaystyle \mathrm{g}=9.8 \mathrm{~ms}^{-2}$)