Correct Answer : Viscous outer core flow
Explanation : Nozzle core flow can be divided into inviscid inner core flow and viscous outer core flow. The viscous outer core flow is also called the mixing layer. No chemical reactions are assumed to take place in the nozzle inner core flow.
Correct Answer : Option (C) : 52.36 m/s
Explaination : Pitch rate q = V/RThen, V = qR = 20 x π/180 x 150 = 52.36 m/s.
Correct Answer : Option (C) : 1.525 hrs
Explanation : T=2π(R0+h)3/2/√μ= 2×3.14x(6728000)3/2/(3.986×1014)= 1.525 hrs.
Correct Answer : Option (D) : Unguided rocket projectiles
Explanation : Unguided rocket projectiles can be given a rotation about its longitudinal axis by means of inclined fins or smaller rocket nozzles to stabilize it. This is an example of spin stabilization.