An opening in a dam is covered with a plate of 1 m square and is hinged on the top and inclined at 60 ⁰ to the horizontal. If the top edge of the gate is 2 m below the water level what is the force required to open the gate by pulling a chain set at 45 ⁰ angle with the plate and set to the lower end of the plate. The plate weighs 2200 N.

Given data: Area of the gate= 1 m ²

Total force on the gate=
   Depth of the centre of pressure
  Distance of the application point of the force from the hinge
Taking moments about the hinge ,

Then, T = 18.66

Answer: 18.66 kN