Can Object A Be Neutral Based on Charge Interactions?

[kickthatbike]

Three objects (A, B, and C) are brought close to each other one at a time. A and B attract, but B and C repel. Simple true/false question involving "is this one positive/negative/etc." What I'm unsure about is whether or not A could possibly be neutral, or more specifically, is there any way to tell with certainty based on the limited information whether or not it IS neutral?

 

[SteamKing]

There are no neutral charges, only positive and negative charges. A neutral particle is neither attracted to nor repulsed by a charged particle.

 

[kickthatbike]

Fair enough. Thank you!

 

[ehild]

Three objects (A, B, and C) are brought close to each other one at a time. A and B attract, but B and C repel. Simple true/false question involving "is this one positive/negative/etc." What I'm unsure about is whether or not A could possibly be neutral, or more specifically, is there any way to tell with certainty based on the limited information whether or not it IS neutral?

A charged object can attract neutral ones by polarizing them. A rubbed plastic rod (or a simple comb) will attract small and light paper pieces. See: http://www.physicsclassroom.com/class/estatics/u8l1c.cfm (experiment with a rubbed balloon and bits of paper). So you are right, A can be neutral, too.

The problem should have been asked about three point-like charged objects.

ehild