Question

A painter sets up a uniform plank so that he can paint a high wall. The plank is 2 m long and weighs 400 N. The two supports holding up the plank are placed 0.2 m from either end. Show that the upwards force on each of the planks is 200 N. Draw a sketch.

Answer 1

The upward force on each supporting plank is 200 N

The given parameters include;

• weight of the plank, W₁ = 400 N

• length of the plank, l = 2 m

• upward force of each supporting plank, = W₂ and W₃

To show that the upward force of each supporting plank is 200 N, make the following sketch.

                 W₂                                                           W₃

                  ↑                                                              ↑                                                              

           -----------------------------------------------------------------------

              0.2m                         ↓                               0.2m

                                              400 N

• The two supporting planks keeps the 2m plank in equilibrium position.
• If the plank is in equilibrium position the sum of the upward forces equals sum of the downward force.

W₂  +   W₃ = 400 N

But the distance of each supporting plank from the end is equal, (0.2m).

Then, W₂  =  W₃

2W₂ = 400 N

W₂ = 400N/2

W₂ = 200 N

W₃ = 200 N

Therefore, the upward force on each supporting plank that keeps the plank in equilibrium position is 200 N.

To learn more about equilibrium forces visit: brainly.com/question/12582625