Exams › NEET › Physics

The frequency of sound observer hears in the echo reflected from the cliff is 838 Hz. Here, original frequency of sound, f₀ = 100 Hz. Speed of source Vₛ = 19.4 cos 60° = 9.7. From Doppler's formula, f' = f₀ (V - V₀) / (V - Vₛ). Calculate the apparent frequency.

1. 103 Hz
2. 1412 Hz
3. 5000 Hz
4. 720 Hz

Correct answer: 1412 Hz

Solution

The Doppler effect formula is applied twice: once for the sound wave traveling to the cliff and once for the echo returning to the observer. Substituting the given values into the formula, the apparent frequency is calculated as 1412 Hz.

Related NEET Physics questions

• In stationary waves, nodes are the points where there is:
• How does the sound produced by a vibrating object in a medium reach your ear?
• is the distance between consecutive corresponding points of the same phase, such as crests, troughs, compressions, rarefactions or zero crossings and is a characteristic of both travelling waves and standing waves, as well as other spatial wave patterns.
• An echo is simply a........of sound.
• The condition for constructive interference is path difference should be equal to :
• In a stationary wave:

⚔️ Practice NEET Physics free + battle 1v1 →