(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

Squids and octopuses propel themselves by expelling water. They do this by taking the water into a cavity and then suddenly contracting the cavity, forcing the water to shoot out of an opening. A 6.50 kg squid (including the water in its cavity) that is at rest suddenly sees a dangerous predator.

If this squid has 1.75 kg of water in its cavity, at what speed must it expel the water to suddenly achieve a speed of 2.50 m/s to escape the predator? Neglect any drag effects of the surrounding water.

2. Relevant equations

m dv/dt=-Vex dm/dt

v-vo- -vex loge (m1/m0)

3. The attempt at a solution

vex= V/ log (m1/M0)

= -2.5 m/s / (log ((6.5-1.75)6.5)

= 7.9704 m/s

Now I figured out this problem based on the equations that i have and this is the only solution that i keep getting. Am I using the wrong equation or am I entering the numbers wrong? Thanks for the help!

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# Homework Help: Impulses of Squids

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