Aski jumper competing for an olympic gold medal wants to jump a horizontal distance of 135 meters. the
takeoff point of the ski jump is at a height of 25 meters. with what horizontal speed must he leave the jump?
a. what do you know?
b. what do you need to solve for?
c. what equation(s) will you use?
d. what is the solution to this problem?

A. We know that the height (h) = 25 m, and the distance (x) = 135 m.

B. We need to find the time flight first (t), then we can find easily the horizontal velocity ( . )

C. Because this is a projectile motions, so horizontal velocity is constant, but the vertical  velocity is change because of the gravitational acceleration.
So we can use : ,

Note : Time that will be exist is a time from a land to the takeoff point, that can be called as the time flight.
Then we use, , to find the horizontal velocity.

D. We know that :
     , so by insert the numbers, and assune that the (g = 10 m/), we get that ( t = . )
     After that by using  , we can get that 

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