Resonance is the response of a standing wave to another wave

a. of a higher frequency

b. of a lower frequency

c. of the same frequency

The modern-day generator works on the principle of electromagnetic induction discovered by michael faraday in 1831-32. faraday discovered that the above flow of electric charges could be induced by moving an electrical conductor, such as a wire that contains electric charges, in a magnetic field.

Answer(b) both involve the use of levers;