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Question
A bat emits an ultrasonic sound of frequency 0.25 MHz. Calculate the time in which one vibration is completed.
Solution
Frequency of ultrasound = ƒ = 0.25 MHz
ƒ = 0.25 × 106 Hz
Time in which one vibration is completed = T = `1/"f"`
T = `1/(0.25 xx 10^6) = 100/25 xx 10^-6`
T = 4 × 10-6s
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