An echo is heard after 5 seconds of the production of sound which moves with a speed of 340 m/s. What Is the distance of the mountain from the source of sound which produced the echo?

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Q: (CDS-II/2019)
An echo is heard after 5 seconds of the production of sound which moves with a speed of 340 m/s. What Is the distance of the mountain from the source of sound which produced the echo?

question_subject: 

Geography

question_exam: 

CDS-II

stats: 

0,13,22,8,13,5,9

keywords: 

{'distance': [0, 3, 3, 3], 'echo': [0, 0, 1, 2], 'km': [0, 0, 2, 1], 'speed': [0, 1, 2, 0], 'sound': [4, 3, 10, 15], 'mountain': [1, 0, 0, 0], 'seconds': [3, 3, 8, 6]}

The correct answer is option 2, which is 0.85 km.

To understand why the correct answer is 0.85 km, we need to use the concept of speed, time, and distance.

The speed of sound in air is approximately 340 m/s. When a sound wave travels from the source to the mountain and then back as an echo, it covers a certain distance twice - once from the source to the mountain and then from the mountain back to the source.

Given that the echo is heard after 5 seconds, we know that the total time taken for the sound wave to travel the round trip (source to mountain and back) is 5 seconds.

Using the formula Distance = Speed × Time, we can rearrange it to get Distance = Speed/2 × Time (since the sound wave travels the distance twice).

Plugging in the given values, Distance = 340 m/s / 2 × 5 s = 170 m.

Converting this distance to kilometers, we get 0.17 km.

Therefore, the distance of the mountain from the source of sound is 0.17 km or 0.85 km (option 2).

Option 1 (0085 km), Option