1. How can a person sing into a piano and cause a piano wire to vibrate? A. The person sings at the same frequency as the piano wire, called the resonance frequency.

B. The person sings at a different frequency than the piano wire, called the beat frequency.

C. The person sings at the same frequency as the piano wire, called the beat frequency.

D. The person sings at a different frequency than the piano wire called the resonance frequency.

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Acave rescue team lifts an injured spelunker directly upward and out of a sinkhole by means of a motor-driven cable. the lift is performed in three stages, each requiring a vertical distance of 10.0 m: (a) the initially stationary spelunker is accelerated to a speed of 4.90 m/s; (b) he is then lifted at the constant speed of 4.90 m/s; (c) finally he is decelerated to zero speed. how much work is done on the 68.0 kg rescue by the force lifting him during each stage?

If y gets smaller as x gets bigger and y have an relationship?

The energy produced as a result of this flow of electrons from atom to atom is called