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) I know that the take off height is 25m. I also know that the horizontal distance to cover is 135m.

b) I need to solve the take off horizontal speed from the height.

c) The equation is Horizontal distance, x =  Horizontal speed u  * time t.
                                                               x  = ut

H = (1/2)gt^2.  Taking g as 10 m/s^2

Where H = Take off height from the ground.

Using second equation:

H = (1/2)gt^2

25 = (1/2)*10* t^2

25 = 5t^2

5t^2 = 25

t^2 = 5.    Therefore,  t = √5  seconds.

Using x  = ut

125  =  u * √5

u = 125/√5.    Expressing as surd u = 25√5  m/s.

Using your calculator,  u = 55.90 m/s.

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