Final answer:
The comb becomes negatively charged after running through hair and attracts small pieces of paper through electrostatic forces. This demonstrates the concept of electric force. However, the movement of a comb cannot produce visible light such as red light due to frequency requirements that exceed manual motion.
Step-by-step explanation:
When a student runs a comb through their hair and then brings it close to small pieces of paper, the small pieces of paper will be attracted towards the comb. This happens because combing the hair transfers electrons from the hair to the comb, resulting in the comb acquiring a negative charge due to the excess electrons. The pieces of paper, being positively charged or neutral, are attracted to the negatively charged comb due to electrostatic forces, a fundamental concept in electric force.
The attraction of paper pieces to the comb after it has been used to comb hair was noted as evidence of the concept of electric force, which underpins many phenomena in the physical world.
Moving a comb fast enough to produce red light involves a different concept, related to electromagnetic waves rather than static electricity, where the movement would need to occur at frequencies in the visible spectrum, which is not feasible with manual motion.