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 planet with a velocity of 3 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 ms−2) is
(Given g=9.8 ms−2)