Squid use jet propulsion for rapid escapes. A squid pulls water into its body and then rapidly ejects the water backward to propel itself forward. A 1.5kg squid (not including water mass) can accelerate at 20 m/s2 by ejecting 0.15kg of water.
What is the magnitude of the thrust force on the squid?
What is the magnitude of the force on the water being ejected?
What acceleration is experienced by the water?
i) F = ma = 1.5kg 20m/s² = 30 N
ii) By Newton’s 3rd, F = 30 N
iii) a = F / m = 30N / 0.15kg = 200 m/s²
Hope this helps!