Sound Physics Example 1

Follow the full solution, then compare it with the other examples linked below.

Example 1

easy
Thunder is heard 6 s6 \text{ s} after lightning is seen. How far away was the lightning strike? Use the speed of sound v=340 m/sv = 340 \text{ m/s}.

Solution

  1. 1
    Light travels almost instantaneously, so the delay is due to the speed of sound.
  2. 2
    Use the distance formula: d=vtd = vt.
  3. 3
    d=340×6=2040 m≈2 kmd = 340 \times 6 = 2040 \text{ m} \approx 2 \text{ km}

Answer

d≈2040 m≈2 kmd \approx 2040 \text{ m} \approx 2 \text{ km}
Sound travels much slower than light. The time delay between seeing lightning and hearing thunder can be used to estimate the distance of the lightning strike.

About Sound

A longitudinal mechanical wave that travels through a medium (solid, liquid, or gas) via alternating compressions and rarefactions of particles.

Learn more about Sound →

More Sound Examples

Example 2 medium

A sound wave in air has a wavelength of [formula]. What is its frequency? Is this audible? Use [form

Example 3 medium

A person shouts toward a cliff and hears the echo [formula] later. How far is the cliff? Use [formul

Example 4 medium

A sonar pulse is sent from a ship and the echo returns [formula] later. The speed of sound in seawat

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