What Is the Clown's Velocity Before Hitting the Net?

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A 75-kg clown jumps from a 35 m high platform, with air resistance exerting a force of 110 N. The net force acting on the clown is calculated to be 625 N, leading to an acceleration of 8.33 m/s². To find the final velocity before hitting the net, the appropriate kinematic equation is suggested, but there are concerns about the signs used for acceleration and displacement. The calculations initially yield an incorrect velocity due to misinterpretation of units and the need to take the square root. Correcting these errors is crucial for arriving at the accurate final velocity.
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Homework Statement


A 75-kg clown at the circus escapes from a tower by jumping from a platform located 35 m above a safety net held by six other clowns. If air resistance exerts a 110 N force on the clown as he falls, what is his velocity just before he hits the net?


Homework Equations


F=mg-air resistance
a=f/m


The Attempt at a Solution


75kg-9.8 m/s^2-110N
735-110
F=625 N

625/75
a=8.33 m/s^2

I am drawing a blank as to what velocity formula I can use in the problem.
 
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Try this one:
$$v_{f}^{2} = v_{0}^{2} + 2a\Delta y$$
Make sure to watch your signs on ##a## and ##\Delta y## though.
 
2(8.33)35m
16.66*35
=583.1 m/s^2
 
a.k said:
2(8.33)35m
16.66*35
=583.1 m/s^2
That's really fast, I think you forgot to take the square root :)

Also your units are for acceleration, not velocity.
 
a.k said:
625/75
a=8.33 m/s^2

I am drawing a blank as to what velocity formula I can use in the problem.

Hey there!
Just wanted to point this out in case you have that picky teacher or professor who devotes their life to signs - in regards to your acceleration, do keep in mind which way the clown is accelerating(you're saying he accelerates upwards with your value).

Other than that, Post #4 is your way to solving this one.
 
Thanks for the help.
 
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