1. The unit of wavelength is:

2. A man blows a whistle and hears the echo from a rock after 3.6 s. Speed of sound in air = 340 m/s. How far is he from the rock?

3. A dolphin emits a 100 kHz click in seawater (speed = 1500 m/s). What is the wavelength?

4. A ship uses sonar; echo returns after 3 s. Speed = 1500 m/s. What is the water depth?

5. A boy is standing 400 m away from a ship. Speed of sound in air = . How long does the sound take to reach him?

6. Speed of sound in steel could be:

7. If frequency = and speed = , wavelength = ?

8. Time period of a wave with frequency is:

9. Wavelength of sound with frequency in air (speed ):

10. What is the frequency of a wave with time period :