امواج اور آواز

A string has a tension of 100 N and a mass per unit length of 0.01 kg/m. What is the speed of a wave on it?

• 1 10 m/s
• 2 100 m/s
• 3 1000 m/s
• 4 50 m/s

What is the fundamental frequency of an open pipe 1 m long? (Speed of sound 340 m/s)

• 1 85 Hz
• 2 170 Hz
• 3 340 Hz
• 4 680 Hz

When the intensity of a sound is doubled, the sound level rises by about:

• 1 1 dB
• 2 3 dB
• 3 6 dB
• 4 10 dB

An observer moves towards a stationary source of sound. The frequency heard is:

• 1 Lower than the source frequency
• 2 Higher than the source frequency
• 3 The same as the source frequency
• 4 Zero

In a standing wave, the distance between two adjacent nodes is:

• 1 One wavelength
• 2 Half a wavelength
• 3 A quarter of a wavelength
• 4 Two wavelengths