How Does Electric Force Affect Acceleration in Charged Objects?

[HaLAA]

Homework Statement

Question: There is a fixed 55 cm long rod (vertical) that is charged uniformly up to +137 nC, Place a 0.5 g plastic 6 cm long stirrer (horizontal) that is charge to +93 nC, 2.3 cm away from the rod

Calculate the Electric force and acceleration on the stirrer .

Homework Equations

E=Q/4piε r√r^2+(l/2)^2
F=qE=ma

The Attempt at a Solution

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[haruspex]

I guess you meant 'finite line', not infinite.
Try a trig substitution for r. What is suggested by the r²+constant part?

 

[HaLAA]

I guess you meant 'finite line', not infinite.
Try a trig substitution for r. What is suggested by the r²+constant part?

Let r =sqrt (l/2) tantheta?

 

[haruspex]

Let r =sqrt (l/2) tantheta?

Looks good.

 

[HaLAA]

Looks good.

Is that reasonable to get a=0.003m/s^2 ?

 

[haruspex]

Is that reasonable to get a=0.003m/s^2 ?

Not sure. Please post what you get algebraically for the solution to the integral.

 

[HaLAA]

Not sure. Please post what you get algebraically for the solution to the integral.

Sorry, I left it at school