Question

A table outfitted with springs on its feet bounces vertically in simple harmonic motion. A cup of coffee is sitting on the table.

Which of the following changes to this system could cause the cup to lose contact with the table?

Check all that apply.

	increase the amplitude
	increase the period
	decrease the period
	decrease the mass of the table
	increase the mass of the table
	change the phase of the motion

What would be your answers if you considered not the cup bottom losing contact with the table but rather the coffee flying out of the cup if the cup is glued to the table?

Check all that apply.

	decrease the mass of the table
	increase the amplitude
	increase the mass of the table
	increase the period
	decrease the period
	change the phase of the motion

Answer 1

As the extra mass ( Here cup of coffee ) added the amplitude of motion increaes. As the period is proportinal to mass, the increases the mass of the system by adding cup of coffee would result in the increases the time peiod of the motion. As period changes the phase of motion changes,

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As mass of coffee separted from the system, the effective mass of the system decreases and hence the period of motion some what decreases. In this case, the change the phase of the motion would takes place as its period changes.