Kavya claps once near a cliff and hears the echo 2 s later. If sound travels at 340 m/s, how far away is the cliff?

Explanation

1. 01

   In 2 s the sound goes to the cliff and back: 340 × 2 = 680 m in all.

2. 02

   The cliff is half of that: 680 ÷ 2 = 340 m.