A person standing at a distance x in front of a cliff fires a gun. Another person B standing behind the person A at a distance y from the cliff hears two sounds of the fired shots after 2s and 3s respectively. Calculate x and y (take speed of sound 320 m/s)

Home » A person standing at a distance x in front of a cliff fires a gun. Another person B standing behind the person A at a distance y from the cliff hears two sounds of the fired shots after 2s and 3s respectively. Calculate x and y (take speed of sound 320 m/s)

Class 10 | ICSE | Physics | Selina | Sound

A person standing at a distance x in front of a cliff fires a gun. Another person B standing behind the person A at a distance y from the cliff hears two sounds of the fired shots after 2s and 3s respectively. Calculate x and y (take speed of sound 320 m/s)

Two of the fired rounds are heard by person B; the first is straight from the gun, while the second is reflected from the cliff.

Given a sound speed of 320 m/s

The time it takes for sound to travel from point A to point B

Distance divided by time equals speed.

(y – x) / 2 = 320

320 $\times$ 2 = (y – x)

640 = (y – x)

After a moment of contemplation on the cliff,

(y + x) / 3 = 320

320 $\times$ 3 = (y + 3)

960 = (y + 3)

By combining equations

y = 1600 / 2

y = 800 m

x=160 m

i

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