Electricity and Charge: Understanding Attraction and Earthed Conductors

[Cici2017]

Homework Statement

Homework Equations

The Attempt at a Solution

I chose B because I thought the positive charges in the insulator would attract the negative charges in the conductor to one side. I do realize that it is earthed for a short time. What difference does it make?

Thank you

 

[mjc123]

What happens when "the insulator is removed"?

 

[Cici2017]

What happens when "the insulator is removed"?

The negative charges redistribute themselves evenly around the conductor?

 

[mjc123]

Yes

 

[Cici2017]

Yes

Oh~so 'earthing' has the same effect as removing the insulator?

 

[mjc123]

No. Earthing allows the (previously isolated) conductor to acquire a negative charge as a result of attraction from the positively charged insulator. Then the Earth is disconnected (the question doesn't say this explicitly, but it is implied in "earthed for a short time") and then the insulator is removed, and the negative charge is redistributed.

 

[Cici2017]

No. Earthing allows the (previously isolated) conductor to acquire a negative charge as a result of attraction from the positively charged insulator. Then the Earth is disconnected (the question doesn't say this explicitly, but it is implied in "earthed for a short time") and then the insulator is removed, and the negative charge is redistributed.

okay, so if the insulator was not removed, the answer would have been B?

 

[mjc123]

Yes

 

[Cici2017]

Yes

Thank you so much!