Skip to content

Why does thunder follow lightning?

Show answer & explanation

Answer: Light faster than sound waves

Thunder causes lightning flash — Wrong. Lightning causes thunder, not vice versa. Electrical discharge heats air explosively—rapid expansion creates thunder shockwave.

Light faster than sound waves ✓ — Correct! Speed difference! Lightning and thunder occur simultaneously, but perceived separately: (1) Lightning—see instantly (light: 300,000 km/s). (2) Thunder—hear delayed (sound: 343 m/s in air). (3) Count seconds between flash and boom—divide by 3 ≈ distance in km (or by 5 for miles). Thunder: rapid air heating from lightning bolt (30,000°C)—explosive expansion creates shockwave. Close lightning: immediate crack. Distant: low rumble (sound waves refract). Can't hear thunder beyond ~25km!

Lightning and thunder are unrelated — Wrong. Thunder is direct result of lightning—electrical discharge superheats air channel, creating explosive expansion we hear as thunder.

Play today's quiz — new questions daily

More Weather & Climate questions