1.A painter of weight 1000N stands 1.0m from the left-hand end of a uniform plank which is 5.0m long and weighs 800N. The plank is supported by two trestles each 0.5m from the opposite ends. The diagram

 

a)Complete the diagram above to show any other forces which are acting on below shows the two upward forces P and Q acting on the plank due to the trestles. Name each of these forces.
(b) What is the magnitude of the total downward force exerted on the trestles?
(c) What is the magnitude of the total upward force exerted by the trestles on the
plank?
(d) By taking moments about the left trestle, calculate the upward force exerted on the plank by the other trestle.

0.5m 0.5m