Helped needed with projectile motion given only angle and x/y distance

AI Thread Summary
The discussion revolves around a physics problem involving projectile motion, specifically calculating the necessary speed for a motorcycle jump across a river. The ramp's angle is 53.0 degrees, with the river being 40.0 m wide and the far bank 15.0 m lower than the ramp. Participants are asked to determine the speed needed at the ramp's top to just reach the far bank and the landing point if the speed is halved. The original poster seeks clarification on the solving method despite already knowing the answers. The thread emphasizes the importance of understanding the physics principles behind projectile motion in this scenario.
TheLunchGun
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1. A physics professor did daredevil stunts in his spare time. His last stunt was an attempt to jump across a river on a motorcycle. The takeoff ramp was inclined at 53.0 degrees, the river was 40.0 m wide, and the far bank was 15.0 m lower than the top of the ramp. The river itself was 100 m below the ramp. You can ignore air resistance.

a. What should his speed have been at the top of the ramp for him to have just made it to the edge of the far bank?

b. If his speed was only half the value found in (a), where did he land?


This problem has been a thorn in my side for many an hour. Some help would be great if anyone has some time.
 
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