Which of the following is not an expression power?

Options

A. `P=VI`
B. `P=I^2R`
C. `P=V^2/R`
D. `P=I/R`

Answer

D

Explanation

Due to the rotation of tube, centripetal force produced in inner liquid and this force produce pressure on B of tube. Hence on the surface of B force is produced. We know that in rotational (circular) motion, formula for centripetal force `F=momega^(2)r" "....(1)`
Now suppose linear density of liquid is `rho` suppose liquid element is dx from distance x from the axis.
Mass of element `dx=dx.A.rho`
(Where A = cross sectional area of tube)
`therefore` Centripetal force produced by dx element of liquid = `dxArhoomega^(2)x`
For whole liquid taking integral from limit 0 to L
Centripetal force `F=underset(0)overset(L)intArhoomega^(2)xdx`
`=Arhoomega^(2)underset(0)overset(L)intxdx`
`=Arhoomega^(2)[x^(2)/(2)]_(0)^(L)`
`=(Arhoomega^(2)L^(2))/(2)`
`=AL(rhoomega^(2)L)/(2)`
`therefore F=(Momega^(2)L)/(2)(because" Mass of liquid "M=ALrho)`