Physics Help Forum General Launch Angle problem

 Kinematics and Dynamics Kinematics and Dynamics Physics Help Forum

 Oct 14th 2016, 08:35 PM #1 Junior Member   Join Date: Oct 2016 Posts: 6 General Launch Angle problem A football quarterback shows off his skill by throwing a pass 45.10 m downfield and into a bucket. The quarterback consistently launches the ball at 39.00 ∘ above horizontal, and the bucket is placed at the same level from which the ball is thrown. What initial speed is needed so that the ball lands in the bucket? R = initial velocity ^2 / gravity * sin2theta, which gives initial velocity needed as 21.3 m/s. By how much would the launch speed have to be increased if the bucket is moved to 48.40 m downfield? I plugged in 48.4 and solved for initial velocity again and came up with 22 m/s but that isn't correct. I also thought maybe it wanted the difference (22-21.3) but that wasn't right either. Is initial launch speed different than initial velocity?
 Oct 14th 2016, 09:08 PM #2 Senior Member     Join Date: Aug 2008 Posts: 113 Without rounding until finished, I get a difference of 0.763962 m/s Try 0.8 m/s ? ilovephysics likes this.

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