Question

Sam combs his hair and brings the comb near some tiny pieces of paper. He finds that the comb is attracting the pieces of paper which is working against the gravity to pull them up. Which force is responsible for the attraction?

• A. Magnetic force
• B. Mechanical force
• C. Nuclear force
• D. Electrostatic force

Answer 1

The correct option is D Electrostatic force

Paper is not a good conductor and is electrically neutral. When Sam combs his hair, the comb gets negatively charged, due to friction between the comb and his hair.
When the comb is brought close to the pieces of paper, electrical charges realign themselves inside the piece of paper. Because of this, an electrostatic force starts acting on the paper pieces and they get attracted towards the comb.
Since the electrostatic force is greater than the gravitational force acting on the paper, it gets attracted against the direction of the force of gravity.