Physics-
General
Easy
Question
A tuning fork of frequency 250 Hz produces 4 beats per second with a wire of length 25 cm vibrating in its fundamental mode. The beat frequency decreases when the length is slightly shortened. What could be the minimum length by which the wire be shortened so that it produces no beats with the tuning fork?
- 0.2 cm
- 0.4 cm
- 0.3 cm
- 0.1 cm
The correct answer is: 0.4 cm
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