Explore BrainMass

Working with an electroscope

Two conducting wires each of length L are connected to a knob, whereby a total electric charge Q is deposited onto two small spherical metallic spheres, each of mass m and diameter d, at the end of the wires. We observe each wire of this electroscope to lie at an angle q from the vertical.

Find an expression for the charge Q in terms of the given quantities L,m,d and q as well as physical constants. You have now calibrated the electroscope, and may use it for quantitative experiments.


Compute the electric field, in both components and as magnitude and direction, at the midpoint between the two hanging masses

Solution Preview

Please view the figure also

When the electroscope is charged, an equal amount of charge is transferred to each of the balls, which repel each other causing the leaves to make an angle with the vertical.
Thus the horizontal forces keeping the balls apart and hence the leaves are the Coulomb forces due to each charged ball. Also, we have to remember that there will consequently be some tension in the leaves of the electroscope which are held at an angle to the ...

Solution Summary

The solution gives all steps along with proper explanations so that you can solve similar problems yourself. All mathematical steps are clearly shown.