Squids and octopuses propel themselves by expelling water. They do this by takin

Question

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 6.40 kg squid (including the water in its cavity) that is at rest suddenly sees a dangerous predator. {Part 1: If this squid has 1.90 kg of water in its cavity, at what speed must it expel the water to suddenly achieve a speed of 2.65 m/s to escape the predator? Neglect any drag effects of the surrounding water.} {Part 2: How much kinetic energy does the squid create for this escape maneuver?} The answer to part 1 is 6.28 m/s, but I cannot get Part 2

Explanation / Answer

m = 6.40 kg

delta V = 2.65 - 0

= 2.65 m/s

change in momentum of squid

= (6.40)(2.65)

= 16.96 kg-m/s

squid's change in momentum = expelled water momentum change

mass of water to be expelled = 1.90 kg

V = 16.96/1.90

= 8.92 m/s ANS

Related Questions

Navigate

• Browse (All)
• Browse S
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.