A ball is launched from the edge of a table which is 2.5 m high. The initial velocity of the ball is 5 m/s at an angle of 30 degrees above the horizontal or table. If the gravitational acceleration is 10 m/s^2 and value of cos 30 degrees is 0.86.(adsbygoogle = window.adsbygoogle || []).push({});

a.)Calculate the flight time in seconds.

b.) Calculate the maximum height H.

c.) Calculate the distance R it travels until the ball reached the ground.

My work:

b.) For the maximum height, I first calculated the time it reaches its velocity at 0 m/s.

So V( x final)= V( x initial) cos 30 * time

But V( x final)= 0

substituting so time= 5 ( 0.86) / 10

= 0.172 seconds as the ball reaches its peak.

then y= V ( x initial) cos 30* time - 1/2 gt^2

=0.59464 + (2.5m because this is the height of the table)

= 25.59 m ( I am not sure if this is correct because I use cosine instead of sine)

I cannot get the value of flight time and the range R. Please help me.

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