Question

A uniform ladder is 10 m long and weighs 400 n. it rests with its upper end against a frictionless vertical wall. its lower end rests on the ground and is prevented from slipping by a peg driven into the ground. the ladder makes a 30ô° angle with the horizontal. the magnitude of the force exerted on the peg by the ladder is:

Answer 1

Answer;

200 N

Solution;

Given ;

Weight = 400 N

Length of the ladder = 10 m

Using the equation;

Torque = d x F, where F is the perpendicular force and d is the distance

Calculating torque about the lower end,

Tweight = Twall

400N(5cos30) = F (10sin30)

 F = 200 N

Therefore, the magnitude of force exerted on the peg by the ladder is 200 N