Question

A sea wave strikes a rock whose two successive crests are 175 m apart. If the crests are moving at
25 m/s. Find out the time in which sea wave strikes the rock again.​

Answer 1

Answer: time is 7s

Explanation:

According to me this question came in the tallentex paper which was held on 20 th this month This was the first question of the paper.

Answer 2

Answer: 7 seconds

Explanation:

The distance between the two successive crests = 175 m

Since we know that the distance between two successive crests equal to the distance between the two successive troughs is known as the wavelength “λ” of the wave, therefore,  

λ = 175 m

The speed of the crests, v = 25 m/s

By using the formula of measuring the velocity of the waves,  

v = λ/T  …… [where T = time period]

rearranging the formula and substituting the given values

⇒ T = λ/v

⇒ T = 175/25

⇒ T = 7 sec

Thus, the sea waves will strike the rocks again after 7 seconds.