Hi, I've been working on my homework assignment, and there are a couple tricky questions that I hope someone can give me a few pointers on.(adsbygoogle = window.adsbygoogle || []).push({});

Question:

Compressed air is used to fire a 60 g ball vertically upward from a 5.3 m tall tube. The air exerts an upward force of 3.3 N on the ball as long as it is in the tube. How high does the ball go above the top of the tube?

I have tried a few things:

First, I tried finding the acceleration in the tube and then using that to find the speed at the end of the tube.

F=ma

a=55.0m/s/s

then vf^2=vi^2+2a*d

vf= 17.38 m/s

Then to find height, I used vf^2=vi^2+2a*d with vf from the tube as the new vi, and vf=0 because it's at the max height.

Using 0=17.38^2+2(-9.8)d

d=15.41 m (which is incorrect)

I also tried d=.5*gt^2 and got d=35m (also incorrect)

If anyone can give me a better direction, I would be very greatful,

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# Homework Help: Force, acceleration, gravity question

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