- #1
oobgular
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Homework Statement
A block has dimensions 0.015 x 0.2 x 0.1 meters and weighs 6 Newtons. A 15mm-diameter jet of water is deflected by the block. Find the flow rate needed to tip the block.
Homework Equations
Mass conservation: ∂/∂t ∫(control volume)ρ d∀ + ∫(control surface) ρv•n dA = 0
Momentum conservation: ∂/∂t ∫(control volume)ρv d∀ + ∫(control surface) ρv(v•n) dA = ∫(control surface) p*ndA + Viscous forces + ∫(control volume)ρgd∀
The Attempt at a Solution
I know this is steady state, so the first term in each equation (time derivative of mass in the control volume) is zero. I am trying to use a control volume that follows the streamlines, to make the surface integrals easier. However, I don't know what area to use as the output, or even how to approach finding it. Also, how should I relate the force on the block to the force required to tip the block? I assume it has to do with a Moment balance, but I'm not sure how to do that.
I don't want you to solve the problem for me, just some direction would be nice. Thanks!