Phase of workdone by water jet by water jet striking flat stationary plate inclined at an angle θ

Q.  Consider the following diagram of jet of water striking flat stationary plate inclined at an angle θ. What will be the phase of workdone on the plate?
- Published on 16 Sep 15
Jet-of-water-striking-flat-stationary-plate-inclined-at-some-angle.png


a. negative
b. positive
c. zero
d. unpredictable

ANSWER: zero
 

    Discussion

  • Pankaj   -Posted on 06 Oct 15
    The given diagram is of water jet striking flat stationary plate inclined at an angle θ.

    Consider,

    V = Velocity of jet, m/s

    A = Cross-sectional area of jet, m2

    ρ = density of fluid, kg/m3

    As the plate is fixed, its velocity is zero.

    Normal force on the plate is given by,

    Fn = ρ A V (V sin θ – 0)

    = ρ A V2 sin θ

    As the plate is stationary and no change in its velocity, the workdone on plate, even if it is inclined, is zero.

Post your comment / Share knowledge


Enter the code shown above:
 
(Note: If you cannot read the numbers in the above image, reload the page to generate a new one.)