A 4.85-kg squid initially at rest ejects 0.26 kg of fluid with a velocity of 10.
ID: 1415461 • Letter: A
Question
A 4.85-kg squid initially at rest ejects 0.26 kg of fluid with a velocity of 10.5 m/s. Randomized Variables m_1 = 4.85 kg m_2 = 0.26 kg v = 10.5 m/s t = 0.095 s F = 4.75 N What is the recoil velocity, in meters per second, of the squid if the ejection is done in 0.095 s and there is a 4.75 frictional force opposing the squid's movement? Use a coordinate system in which the ink is moving in the positive direction. What is the difference in kinetic energy, in joules, between the case when there is no friction and the care where friction? E_lost =Explanation / Answer
ms = mass of squid = 4.85 kg
mf = mass of fluid = 0.26 kg
Vs = recoil velocity of squid = - (0.26) (10.5) /(4.85 - 0.26) = - 0.595 m/s
when the motion is opposed by frictional force
Vs' = [4.75 (0.095) - (0.26) (10.5)] /(4.85 - 0.26) = - 0.496
b)
Change in KE = (0.5) (4.85 - 0.26) [( - 0.496)2 - ( - 0.595 )2] = - 0.25 J