# Operations on Real Number

1) Puja Is Going to Visit a Forest With His Father. In This Forest, an Elephant Produces a Sound With a Frequency of 15 Hz. Assuming the Speed of Sound in Air Is 450 m/S, Determine the Wavelength of This Sound Wave.

Frequency of the sound = 15 Hz
Speed of sound = 450 m/s
Then from the formula of the speed of sound, we have,

Speed = Wavelength × Frequency
From this,

Wavelength Speed/Frequency

Wavelength 450/15m

Wavelength = 30 m

The wavelength of the sound is 30m.

2) Raja Is Going to Visit a Zoo With His Father. In This Zoo, a Tiger Produces a Sound With a Frequency of 20 Hz. Assuming the Wavelength of This Sound Is 25 m, Determine the Speed of Sound in the Air.

Frequency of the sound = 20 Hz
Wavelength = 25 m
Then from the formula of the speed of sound, we have,
Speed = Wavelength × Frequency
Speed = (25 × 20) m/s
Speed = 500 m/s
The speed of the sound in the air is 500 m/s.

3) On a Hot Summer Day, a Pesky Little Mosquito Produced Its Warning Sound Near Your Ear. The Beating of Its Wings produces the Sound. Assuming the Speed of the Sound Is 300 m/S and the Wavelength of the Sound Wave Is 10m, Determine the Frequency

The wavelength of the sound wave = 10 m
Speed of sound = 300 m/s
Then from the formula of the speed of sound, we have,
Speed = Wavelength × Frequency
From this,

Frequency= Speed/Wavelength

Frequency= 300/10Hz

Frequency = 30 Hz

So, the Frequency of the sound is 30 Hz.