Physics
(a) One end of a plastic foot ruler is held tightly at the edge of a table and the other end is plucked. Name the vibrations produced in the ruler.
(b) Now the ruler is pushed inside partially and plucked again from its freе end. State with a reason whether the frequency of vibration increases or decreases.
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Answer
(a) When one end of the plastic ruler is held firmly at the edge of the table and the other end is plucked, the ruler vibrates on its own after being displaced and these vibrations are called natural vibrations.
(b) The frequency of vibration increases because when the ruler is pushed further inside, the length of the free vibrating part decreases and since a shorter vibrating length oscillates more rapidly, so the frequency increases.
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