GATE Exam Questions - Engineering

Q1:

In a steady radial flow into an intake, the velocity is found to vary as (1/r2), where r is the radial distance. The acceleration of the flow is proportional to

A 1/r5

B 1/r3

C 1/r4

D 1/r

ANS:A - 1/r5

a= v(dv/ds) + dv/dt

As steady flow is taking place, dv/dt=0.
a= v (dv/ds).
now, v= k/r2.
dv/ds= dv/dr= -2k/ r3.
therefore, a varies as 1/r5.