I with Fluid systems question

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The problem involves calculating the tension in a horizontal cable attached to a sluice gate retaining water in a rectangular channel. The thrust on the gate, calculated using the formula F = pgAh, yields a value of 18.3 kN based on the given water density and depth. However, the thrust calculation assumes the gate is horizontal, while the gate is actually vertical, necessitating a different approach. The situation requires analyzing the statics of a vertical bar under a distributed load, with the cable providing a counteracting force. Further guidance is needed to correctly determine the tension in the cable.
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Homework Statement



Water is retained in a 1.25 rectangular section channel by a sluice gate. This gate can pivot about its base, the depth of the water is 1.5m and the density of the water is 1000kgm^-3. You must find the tension in the horizontal retaining cable attached to the top of the gate.

Homework Equations



Thrust: F= pgAh
Gravity = 9.81

The Attempt at a Solution



Provided data:
Retained water 1.25
Density: 1000kgm^-3
Depth: 1.5m
Gravity: 9.81

So this is what i did, first i found the thrust of the gate so:
F=1000 x 9.81 x 1.5 x 1.25 = 18393.75 so 18.3 x 10^3 or 18.3 kN

I'm not sure though if this is right or what to do next to find the tension, could someone help me on this please
 
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The formula for thrust is correct only if the gate is horizontal at the bottom of the channel. From the description, however, it appears that that the gate is vertical.

The problem is that of statics, with a distributed load applied to a vertical bar hinged at the bottom, and a point force provided by the cable.
 
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