- 65

- 0

upward at an angle of 47 ◦ to the horizontal

and with an initial speed of 23 m/s, as in

the figure. The ball is thrown at a height of

46 m above the ground and hits the ground

82.0127 m from the base of the building.

The acceleration of gravity is 9.8 m/s2 .

What is the speed of the ball just before it

strikes the ground?

Answer in units of m/s.

I have tried calculating the max height (14.4363m) and the time @ max height (1.71644s) then doing vf-=vi-gt => vf=-9.8(1.71644)=-16.8211 m/s (wrong)

not sure what else to try...