A triangular plate with height 6 ft and a base of 8 ft is submerged vertically in water so that the top is 3 ft below the surface. How do you express the hydrostatic force against one side of the plate as an integral and evaluate it?

A triangular plate with height 6 ft and a base of 8 ft is submerged vertically in water so that the top is 3 ft below the surface. Express the hydrostatic force against one side of the plate as an integral and evaluate it. (Recall that the weight density of water is 62.5 lb/ft3.)

1 Answer

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Explanation:

It's 93 43 δ (9 - x)x dx. Solving it gives us:

= 43 95 δ (9 - x)x dx

= 43 δ 93 9x - x2 dx

= 43 δ [92 x2 - 13 x3 ]93 dx

= 43 δ [92 92 - 13 93 - (92 32 - 13 33)]

= 43 δ [92 81 - 13 729 - (92 9 - 13 27)]

= 43 δ [7292 - 7293 - (812 - 273)]

= 43 δ [7292 - 7293 - 812 + 273]

= 43 δ [7292 - 812 - 7293 + 273

= 43 δ [6482 - 7023]

= 43 δ [6482 - 7023]

= 43 δ [324 - 234]

= 43 δ [90]

= 3603 δ

= 120 δ

Note that δ is the weight of density of water. Now we must use δ = 62.5

= 120(62.5)

= 7500