- #1

Agent M27

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## Homework Statement

A 3.72 kg steel ball strikes a massive wall at 15.1 m/s at an angle of 58.6 with the plane of the wall. It bounces off with the same speed and angle. If the ball is in contact with the wall for .198s what is the average force exerted on the ball by the wall? Answer in units of N.

The picture is depicted with the wall along the y-axis and the ball is originating from the 3rd quadrant with an angle of 58.6 between the trajectory and the negative x axis. It then bounce off and continues into the second quadrant making the 58.6 angle with the negative x-axis again.

## Homework Equations

(1) [tex]\Delta[/tex]P

_{x}= -mv

_{f}cos[tex]\theta[/tex]-mv

_{i}cos[tex]\theta[/tex]

(2) [tex]\Delta[/tex]P

_{y}= mv

_{f}sin[tex]\theta[/tex] - mv

_{i}sin[tex]\theta[/tex]

(3) F

_{avg}=[tex]\frac{dP}{dt}[/tex]

## The Attempt at a Solution

So I began by using EQ 1 and subbing in known values and arrived at an answer of -58.53231 N s. I then use that value in EQ 3 and arrive at a final answer of -295.61771 N. The online module doesn't give me the correct answer but says this is incorrect. Where am I going wrong? Thanks

I also tried using the angle between the y-axis and the trajectory which gave me an angle of 31.4. This yielded an answer of -95.89 N s. Subbing that into EQ 3 I get an answer of 484.2995 N, yet again this is wrong...

Joe