The speed per hour of A is 36km/h and the speed per hour of B is 27km/h.
A rang a whistle and B which heard A's whistle rang a whistle immediately.
The whistle of B has reached A 17 seconds later after A rang a whistle.
The speed of sound is set to 340 m per second.
How many seconds later was it that B heard A's whistle after A rang a whistle?
Answer
8.75 seconds
Solution
The speed per second of A is 36/3.6 = 10m/s.
Answer
8.75 seconds
Solution
The speed per second of A is 36/3.6 = 10m/s.
Total distance traveled by A and whistle in 17 seconds is (340 + 10) × 17 = 5950m.
The distance that A's whistle reached B is 5,950/2 = 2,975m.
The time when A's whistle went ahead through this distance is 2,975/340 = 8.75 seconds.
