You notice the flagpole at school vibrating in the breeze. You count the vibrations and find that the flagpole makes 20 complete vibrations in 10 seconds. You read somewhere that this
lagpole vibrates at a speed of 25 m/s when the wind is blowing Find the wavelength of these
vibrations

12.5m

Explanation:

Given the following :

Flagpole makes 20 complete vibrations in 10 seconds

Velocity (V) of vibration = 25m/s

Find the wavelength of vibration (λ) =?

Frequency is number of complete oscillation per Second

Therefore ;

Frequency (F) = number of oscillations / time taken

F = 20 / 10 = 2Hz

Wavelength = Velocity / frequency

Wavelength = 25 / 2

Wavelength = 12.5m

i think its c if i'm wrong

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