Question

The sound from the siren of a ship is reflected by a cliff.An echo is heared by a sailor on the deck of the ship, 4.0s after the siren is sounded.The speed of sound in air 320m/s.How far from the cliff is the ship? A)80m.B)160m.C)640m. D)1280m​

Answer 1

Provided that:

• The sound from the siren of a ship is reflected by a cliff.

• Time = 4.0 seconds.

• Speed of sound = 320 mps.

To calculate:

• The distance

Solution:

• The distance = 640 m

Using concept:

• Distance formula

Using formula:

• Distance = Speed × Time

Knowledge required:

The sound from the siren of a ship is reflected by a cliff. Therefore, total distance becames 2d.

Required solution:

~ By using suitable formula let us solve this question!

»»» s = v × t

»»» Distance = Speed × Time

»»» 2s = v × t

»»» 2Distance = Speed × Time

»»» 2Distance = 320 × 4

»»» 2Distance = 1280

»»» Distance = 1280/2

»»» Distance = 640 m

• Henceforth, distance = 640 m.

Therefore, the cliff is 640 m far from the ship. Henceforth, option (c) is correct. $\:$

Additional information:

$\begin{gathered}\boxed{\begin{array}{c|cc}\bf Substance &\bf Speed_{(sound)} \: in \: ms^{-1} \\\frac{\quad \quad \quad\quad\quad \quad\quad\quad}{}&\frac{\quad \quad \quad\quad\quad \quad\quad\quad}{}\\\sf Alluminium &\sf 6420 \\ \\ \sf Brass & \sf 4700 \\ \\ \sf Steel & \sf 5960 \\ \\ \sf Iron & \sf 5950 \\ \\ \sf Glass & \sf 3980 \\ \\ \sf Oxygen & \sf 316 \\ \\ \sf Air & \sf 346 \end{array}}\end{gathered}$