Velocity leaving a cannon, hitting landing cushion, and acceleration experienced

AI Thread Summary
The discussion focuses on calculating the velocity of a stuntman shot from a cannon and the acceleration experienced during the launch. The cannon is 3 meters long and angled at 35 degrees, with a landing cushion 30 meters away. Initial calculations yielded an initial velocity of 17.7 m/s, but discrepancies arose regarding the correct acceleration, which was suggested to be calculated using the cannon's length instead of the distance to the landing cushion. The correct approach emphasizes using the cannon's length of 3 meters to determine acceleration, leading to different results than initially obtained. Accurate calculations are essential for determining the stuntman's velocity upon landing and the acceleration during the cannon shot.
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Homework Statement


An 80 kg stuntman is shot from a cannon at a circus. The cannon is 3m in length and angled at 35 degrees above the level floor. The landing cusion is 30m away from the cannon. What velocity will the stuntman have 1)when he leaves the cannon and 2)when he first hits the landing cushion? What acceleration must the stuntman experience in the shot from the cannon? Ignore air resistance.


Homework Equations



Vo=\sqrt{dg/sin2\Theta}
Vo2=2a\Deltax


The Attempt at a Solution


My solutions are higher then the answers given. When i calculated initial velocity (for being shot out of the cannon?) i got 17.7 m/s. that was using d=30m, g=9.81 divided by sin 2(35). Using that number i got the acceleration to be 5.22m/s, for that one i believe the answer is around 52 m/s. I don't know exactly how to get the velocity at the landing cushion.

Any help is much appreciated!
 
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The cannon barrel is only 3.0 meters long.

You used 30 meters to find the accelerstion.
 
alright, using 3m as the range for the range equation i got an initial velocity of 5.8m/s, but that got me an even smaller acceleration.
 
Assuming that v0 = 17.7 m/s is correct (and it appears that it is) then to find the acceleration experienced by the stunt man while he id in the cannon, use:

v02 = 2 acannon Δxcannon.

For this part, use 3.0 meters. (You apparently used 30 meters.)
 
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