A mechanical disturbance is to propagate through a material medium as a wave. The particles of the medium are not transported permanently with the disturbance; instead, each particle oscillates about its equilibrium position while the disturbance moves forward. Which pair of properties of the medium is fundamentally responsible for this propagation?
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Question

A mechanical disturbance is to propagate through a material medium as a wave. The particles of the medium are not transported permanently with the disturbance; instead, each particle oscillates about its equilibrium position while the disturbance moves forward. Which pair of properties of the medium is fundamentally responsible for this propagation?

Options

G1 Physics · Accepted Answer

For a mechanical wave to propagate, neighbouring particles of the medium must be able to exchange energy. Elasticity provides the restoring force that tends to bring a displaced particle back towards equilibrium. Inertia allows the particle to continue moving through equilibrium and transfer the disturbance to neighbouring particles. Therefore the two essential material properties are inertia + elasticity. Correct option: A.