Question

A uniform ladder 3 m long weighing 20 kg leans against a frictionless wall. Its foot rest on a rough floor 1 m from the wall. The reaction forces of the wall and floor are

• A. zero
• B. $50\sqrt{2}N,203N$
• C. $203N,25\sqrt{2}N$
• D. $203N,50\sqrt{2}N$

Answer 1

The correct option is A zero

As one force is acting perpendicular to the wall and the other at certain point.

This creates a pivot if the ladder falls down.

So thee $F_2$ force is resolved in two forces; one that acts normal to the floor and the other which keeps it from falling that is opposite to the $F_{1}so for the ladder to be in vertical equilibrium the vertical forces should cancel out..

Thus W-N=0

Similarly for horizontal, the forces acting horizontally should cancel out.

So F-$F_1$=0