# Homework Help: Tsunami energy calc

1. Jul 24, 2013

### Dastan

1. The problem statement, all variables and given/known data

I was given data of a tsunami height,width & wave length & is asked to calculate total energy of the Tsunami meaning both Potential & Kinetic energy.

Here length of wave = 5 km,height = 2 km & width = 1.5 km. Also ocean depth is 3.5 km.

2. Relevant equations

I don't know what equation I should use to calc the energy.I did found this thread but quite frankly I can't make heads or tails about I should do.

2. Jul 24, 2013

### SteamKing

Staff Emeritus
Tsunamis form only in shallow water, not in the middle of the ocean. The disturbance which eventually results in the formation of a tsunami propagates at high speed in mid-ocean but with a very small wave height.

I don't know where you got your numbers, but they are just numbers and don't represent any real water waves, tsunami or otherwise.

3. Jul 24, 2013

### haruspex

As mentioned at post #15 of the thread you cited, most of the energy is merely the potential energy of that volume of water lifted to that average height. I believe you can ignore kinetic energy - remember that the water does not move en bloc at the speed of the wave.
Are you sure about that height? 2m seems plenty, unless this is an asteroid impact.
That depends on what you mean by a tsunami. Originally it would have referred only to the coastal manifestation, but I would have thought that nowadays it would be taken to mean the entire event, right from its trigger.