Question

A river `10 m` deep is flowing at `5ms^(-1)`. The shearing stress between horizontal layers of the rivers is (`eta=10^-(3) SI` units)
A. `10^(-3)N//m^(2)`
B. `0.8xx10^(-3)N//m^(2)`
C. `0.5xx10^(-3)N//m^(2)`
D. `1 N//m^(2)`

Answer 1

Correct Answer - C
Shearing stress`=(|"viscous force"|)/("area")`
`=(etaA(dv)/(dx))/A=eta(dv)/(dx)`
`10^(-3)xx5/10N/m^(2)=05.5xx10^(-3)N//m^(2)`