How Fast Was Randy Barnes' Record-Setting Shot Putt?

AI Thread Summary
Randy Barnes set a world record shot put distance of 23.12 meters in 1990, requiring an estimated projection speed of 14 m/s when released at a 45-degree angle from a height of 2.2 meters. The discussion involves calculating the speed and the total work done on the shot, which weighs 2 kg, assuming it was initially at ground level. Participants are encouraged to show their calculations for better assistance, as resolving vector components is crucial for accuracy. The back of the book confirms the 14 m/s speed, prompting questions about the calculation methods used. Clear step-by-step work is essential for understanding and verifying the results.
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Q1. A world record for the shot putt of 23.12 m was set by Randy Barnes in Los Angeles in 1990. Estimate the speed at which the shot had to be projected to reach this distance, assuming that the shot was released at 45 degrees to the horizontal from a height of 2.2m above the ground. (The ground is horizontal).

Q2. If the mass of the shot in part A was 2kg, find the total work done on it by Barnes in picking it up and projecting it, assuming that it was at ground level before he picked it up.




2. h=1/2gt^2 S=ut + 1/2 at^2



3. I resolved the vectors into the x and y coordinates but I'm not sure what I'm doing wrong as the back of the book has an answer of 14 m/s for the first part.

Thanks anyways!
 
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Did you combine the x and y components of the velocity vector and find its magnitude?

Also, it'd be nice to show your work ;-) it's going to be hard to help you otherwise.
 
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