The maximum horizontal range of a projectile is given by the formula R=u^2/g, where u is the initial velocity and g is the acceleration due to gravity. Find the velocity with which a ball can be thrown to have a maximum range of 20 meters when the acceleration due to gravity is equal to 9.8 m/s.

My answer: 20=u^2/9.8
118=u^2
u=10.8

Am I correct?
Thanks For Checking

Question

The maximum horizontal range of a projectile is given by the formula R=u^2/g, where u is the initial velocity and g is the acceleration due to gravity. Find the velocity with which a ball can be thrown to have a maximum range of 20 meters when the acceleration due to gravity is equal to 9.8 m/s. 

My answer: 20=u^2/9.8
                  118=u^2
                  u=10.8

Am I correct? 
Thanks For Checking

sshayer · Answer

$$R=\frac{ u^2 }{ g },u^2=R*g$$
$$u^2=20*9.8=196,u=\sqrt{196}=14m/s$$