Question

The speed of sound in air is 320 ms–1 and in water it is 1600 ms–1.
(i) Find the ratio of distance travelled by sound in air and in water.
(ii) Find the ratio of time in air and water to travel the same distance.

Answer 1

Answer:

1. 1/2

2. 2/1

Explanation:

Ratio of distances =

$\frac{320 \times x}{1600 \times x}$

where x is the time ......

so, ratio = 1:2

$\frac{1}{2}$

Similarly , ratio of time is 2:1

Answer 2

(i) 1 : 5

(ii) 5 : 1

Explanation:

The speed of sound in air is 320 ms–1 and in water it is 1600 ms–1.

Distance = speed * time. Let time be x.

(i) Ratio of distance travelled = speed in air / speed in water = 320 / 1600 = 1 / 5

Ratio of distance travelled in air : Ratio of distance travelled in water :: 1:5

(ii) Now assuming distance is constant d, the ration of time taken in air and water for the same distance will be,

Ratio of time taken = time in air / time in water = (x/320) / (x/1600) = 5 / 1

Ratio of time taken in air : Ratio of time taken in water :: 5:1