Physics Practice: Sound (Mock Test 3 - Advanced)
1. A ship sends an ultrasonic signal to the seabed which returns after $4 \text{ seconds}$. If the speed of sound in seawater is $1500 \text{ m/s}$, the depth of the sea is:
2. When we tighten the string of a guitar, the pitch of the sound produced ________.
3. Sound waves show the phenomenon of ________ which is used by bats to catch prey.
4. The ratio of the speed of an object to the speed of sound in air is called the ________ Number.
5. "Amplitude" of a sound wave determines its ________.
6. A person standing between two parallel cliffs fires a gun. He hears the first echo after $2 \text{ s}$ and the second after $3 \text{ s}$. The speed of sound is $340 \text{ m/s}$. The distance between cliffs is:
7. Ultrasonic waves have frequencies greater than ________.
8. Which component of a sound wave represents a region of high pressure?
9. The frequency of a tuning fork depends on its ________.
10. To reduce "Noise Pollution," which of the following is an effective measure?
11. A vibration with a high frequency produces a sound with a ________.
12. The speed of sound in air ________ as the temperature increases.
13. Which instrument works on the principle of reflection of sound?
14. The sensation of sound persists in the human brain for about ________ of a second.
15. A note of sound is a ________.
16. The units used to express the intensity of sound are ________.
17. Infrasonic waves have a frequency ________ $20 \text{ Hz}$.
18. The speed of sound in hydrogen gas is ________ than in air.
19. We hear a clap of thunder after seeing the flash of lightning because ________.
20. Which material is a good absorber of sound?