Squids and octopuses propel themselves by expelling water. They do this by keeping water in a cavity and then suddenly contracting the cavity to force out the water through an opening. A 7.50 kg squid (including the water in the cavity) at rest suddenly sees a dangerous predator.

A. If the squid has 1.55 kg of water in its cavity, at what speed must it expel this water to suddenly achieve a speed of 2.60 m/s to escape the predator? Neglect any drag effects of the surrounding water.

B. How much kinetic energy does the squid create by this maneuver?

a. 9.9806 m/s

b. 97.31J

Explanation:

Mass of squid with water in cavity is M=7.5kg, the water has a mass of and the squid's velocity after releasing the water is

a. The total momentum of a system is the vector sum of its individual particles momenta;

,

#For an isolated system, the momentum is conserved, p=k

#We neglect any external forces such as drag effects:

#mass of the squid:

#For momentum,

#The momentum for the squid initially at rest is zero;

From the equation

Hence, water is expelled at a speed of 9.9806m/s( in opposite direction).

b. We use the mass and velocity of the squid to calculate it's kinetic energy:

The kinetic energy of the water is :

Total kinetic energy:

Hence, the kinetic energy created by the squid is 97.31J

their crystal patterns have been disrupted by stress

im sorry i dont know