At what height h above the ground does the projectile have a speed of 0.5v?
express your answer in terms of v and the magnitude of the acceleration of gravity g.

Explanation:

It is given that,

Speed of the projectile is 0.5 v. Let h is the height above the ground. Using the first equation of motion to find it.

Initial speed of the projectile is v and final speed is 0.5 v.

g is the acceleration due to gravity

Let h is the height above the ground. Using the second equation of motion as :

So, the height of the projectile above the ground is . Hence, this is the required solution.

fgravity=10x10=100n case 1

fgravity=30x20=600n case 2

6 times more

the answer is a. hope this .