Explain how the potential difference across the resistor and the lamp will change when the switch is closed? The resistor

The lamp

This is what a calorimeter is used for simpler ex, to measure calories in food.

Answer(a)   the matererials that are in contact, the two materials and the nature of their surfaces/// (b)/// the force pushing the two surfaces together, pushing the surfaces together causes the more of the asperities to come together and increases the surface area in contact with each other

The anwser is: wave a has a greater pitch and frequency.