A student combed his hair. Then he observed what happened to the water when he put the comb near the faucet as shown below.

Why did the water's path change?

Due to conduction, the charged comb attracted the neutrally charged water
Due to induction, the charged comb repelled the neutrally charged water
Due to conduction, the charged comb repelled the neutrally charged water
Due to induction, the charged comb attracted the neutrally charged water

1 answer

The correct explanation for why the water's path changed when the charged comb was brought near it is:

Due to induction, the charged comb attracted the neutrally charged water.

Here's the reasoning behind this:

  1. When the student combed his hair, the comb likely became charged through the process of triboelectric charging (friction).
  2. When a charged object (the comb) is brought near a neutral object (the water), the electric field of the charged comb induces a separation of charges in the neutral object.
  3. In the case of water, which is a polar molecule, the side of the water molecules closest to the charged comb will experience a slight positive charge (due to the attraction of the negative side of the water molecule towards the positively charged comb). This leads to a polarization where the water molecules are attracted to the charged comb.
  4. As a result, the water's path appears to change towards the comb.

Therefore, the correct option is that the charged comb attracted the neutrally charged water due to the process of induction.