(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

A small, plastic sphere of mass m = 126 g is attached to a string as shown in the figure.

There is an electric field of 151 N/C directed along the + x axis. If the string makes an angle 30 with the y axis when the sphere is in equilibrium, what is the charge on the sphere?

2. Relevant equations

3. The attempt at a solution

mg = 0.126kg * 9.81m/s^2 = 1.24 N

To make an angle of 30 degrees, the horizontal force must be 1.24 N * sin30 = 0.62 N

So then i did .62 N/151N/C = .0041 C or 4.1 mC which is the units they want, i entered it but this isnt correct.

Can someone tell me where i went wrong?

1. The problem statement, all variables and given/known data

2. Relevant equations

3. The attempt at a solution

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# Homework Help: How to find a charge on a sphere in equilibrium?

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