- #1

Dazed&Confused

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## Homework Statement

In deep water, it can be shown that ##\omega = \sqrt{gk/2}##

Orcas (killer whales) have been filmed generating waves in deep water to knock seals off ice floes. Assume that an orca can generate a wavepacket which is simply half a sine wave (i.e. ##\sin(kx)## from ##kx =0## to ##kx= \pi##). Show that the kinetic energy density in this wave can be written: $$U = \frac{1}{32} \rho g \frac{A \lambda}{\pi^2}$$

## Homework Equations

## The Attempt at a Solution

After several attempts, I seem to have noticed a discrepancy. I would assume that energy density has the units ##\text{Jm}^{-3}## or ##\text{kgm}^{-1} \text{s}^{-2}.## The equation has the units ## \text{kgm}^{-3} \text{ms}^{-2} \text{mm }## or ##\text{kgms}^{-2}##, assuming A has the unit of metre.

Are my assumptions wrong?