I missed a few days of class and have a quiz tomorrow so I'm not entirely sure where to start with this. The question is:(adsbygoogle = window.adsbygoogle || []).push({});

A golfer hits a ball (m = 38 g) from a cliff top (h = 46 m) and times how long it takes to splash in the ocean (t = 7.0 s). The ball hits the water at a distance (x = 154 m) from the vertical cliff bottom. Find the ball's initial velocity and the angle of launch.

I have y = 46 m, x = 154 m, t = 7.0 s

I assume I have to use the two-dimensional kinematic equations, but I just can't seem to get anywhere towards finding the initial velocity.

My first thought was

x = v_0x * t

v_0x = 154 / 7 = 22 m/s

Then take

y = (v_0y)t+1/2 gt^2 = 7(v_0y) - 240.34

v_0y = 40.905

And then square both of those and take the square root. But the answer I get doesn't agree with the instructors, so I'm lost.

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# Homework Help: Projectile Motion Ball off Cliff Help

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