A student stands 165 meters away from a tall vertical wall and claps their hands loudly. If the speed of sound in air is 330 m/s, how much time elapses between the clap and the student hearing the echo?

Answer as guest — Start Free Practice Test to earn Practice PointsHow to earn pointsAsk a question+3Answer a question+1Someone answers yours+1Your Q gets upvoted+1Pioneer bonus (first 5)+5, ask questions & climb the leaderboard!

A 0.5 seconds
B 1.0 second
C 1.5 seconds
D 2.0 seconds

Show answer and explanation

Answer: B. 1.0 second

For an echo, the sound travels to the wall and back: 2 × 165 m = 330 m. Time = distance ÷ speed = 330 m ÷ 330 m/s = 1.0 second.

Answering after opening this box earns no Practice Points.

Rules for asking and answering

A student stands 165 meters away from a tall vertical wall and claps their hands loudly. If the speed of sound in air is 330 m/s, how much time elapses between the clap and the student hearing the echo?

More questions like this