You double your distance from a sound source that is radiating equally in all directions. What happens to the intensity level of the sound? It drops by:
The fundamental note produced by a closed pipe in a piano is 128 Hz.
What is the wavelength of its first overtone?
7.2 m.
0.72 m.
2.01 m.
0.52 m.
Which of the following waves CANNOT be polarised?
Ultraviolet radiation
Ultrasonic waves
Radio waves
A horizontal string plucked vertically in the middle
Sound vibrations with frequencies greater than 20,000 Hz are called:
A small vibrating object on the surface of a ripple tank produces waves of frequency 20 Hz and speed 60 cm/s. If the source S is moving to the right as shown the figure, with a speed of 20 cm/s.
What frequency would an observer at point C hear?
30 Hz.
60 Hz.
6.7 Hz.
13.3 Hz.
