Question

1.When a tsunami wave approaches the coast :
- Does speed ​​increase or decrease ?
- Does height increase or decrease ?
- Does wavelength increase or decrease ?

Explain why.

Answer 1

1). Tsunami waves are the seismic waves that are produced during an earthquake beneath the ocean. There are certain way to distinguish the tsunami wave from that of normal waves, and our easy answer would the height. But how it happen it is explained below,

• (Speed decreases) The speed of the waves depends upon the depth of the water that is in between the ocean the velocity of the wave is higher, but as it approaches towards the coast the velocity decreases.
• (Height increases) The energy flux of a tsunami and the wave height always remains constant but as the speed diminishes and it approaches towards shallow coast its height increases and finally breaker becomes more devastating.
• (Wavelength decreases) Similarly from the point of origin of tsunami wave initially the wavelength is very high and one the main reason is higher depth of the water, but as we move shallower towards to coast the wavelength decreases.
• (Period shorten). Period refers to the time passage of 1 particular wavelength. So as we move toward the coast the wavelength of the wave decreases and thus with respect to it the period will also decrease. Hence we can the period shorten.