Question

for resonance which must tally ​

Answer 1

answer : option (b) frequency

explanation : resonance occurs when frequency made from outside source of an oscillating system is same as its own natural frequency.

in simple language,

when the frequency of a vibrating body is equal to the natural frequency of another body then transfer of energy between the bodies is maximum and other body vibrates with a greater amplitude. This phenomenon is known as resonance.

here it is clear that for resonance frequency must tally.