Two glass rods are rubbed together. One of the glass rods are brought near (but does not touch) an uncharged pith ball. Would you expect the pith ball to attract,
repel, or do nothing? Explain why.

The correct answer is - do nothing.

Explanation:

If two same or identical objects, in this instance two glass rods, were rubbed together they neither attract nor repel each other as there is no transfer of electrons from one material to the other material as there is no difference in their charges.

Only two different objects are able to transfer electrons from one material to the other material if rubbed together, to produce the conditions for static electricity to be observed. Therefore there would be no charge on the glass rod so there would be no charge to balls to repel or attract.

when a device is used in a circuit in which the voltage is 81 v, the current flowing through the device is 3 a. what is the resistance of the device?

a. 27 ω

b. 40.5 a

c. 243 ω

d. 243 a

the correct answer is a. 27