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Answer:
72 kilometres per hour
Explanation:
The formula for calculating speed is distance/time.
So to work this out you would convert 2 minutes into hours. You would divide 2 by 60 to convert it into hours. This is because the standard unit for speed with kilometres is kilometres per hour. Then you would divide 2.4 by that.
1)Divide 2 by 60:

2) Divide 2.4 by 0.0333333.

3) Round it.

Answer: 47.6 m/s
Explanation: Please see attached for the calculation and formula.
Answer:
Noise cancelling headphones have a microphone which listens to the ambient noise. The headphone then processes the sound and provides a wave to produce destructive interference. This cancels the ambient noise.
Explanation:
First, let us understand what interference is. Interference is the phenomenon that occurs when two waves superpose to form a wave which has a different wavelength, frequency, amplitude than the original two waves. When the crest of one wave superposes with the other waves crest then this results in the amplitude increasing. This is known as constructive interference. When the crest of one wave superposes with the other waves trough then this results in the amplitude decreasing. This known as destructive interference.
Noise cancelling headphones have a microphone which listens to the ambient noise. The headphone then processes the sound and provides a wave to produce destructive interference. This cancels the ambient noise.
Answer:
size of insect = wavelength = 16.1 mm
Explanation:
Since the bat can detect the size of small insects which are of size equal to the wavelength of sound in air
So here we can say that the wavelength of sound is the ratio of speed of sound and its frequency
here we know that
speed of sound in air is 536 m/s
frequency of sound is 33.3 kHz
so here we can say



