Ladder horizontal force problem

AI Thread Summary
To solve the ladder problem, first identify the forces acting on the ladder, including the weight of the ladder and the painter, and the forces from the wall and ground. The horizontal force exerted by the wall can be calculated using the equilibrium conditions, specifically considering the moments around the base of the ladder. The vertical force from the ground must balance the total weight of the ladder and the painter. Drawing a diagram can help visualize the forces and their directions, which is crucial for resolving the vectors correctly. Understanding the center of mass and applying equilibrium principles will lead to the correct answers for both the horizontal and vertical forces.
tahyus
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1. A uniform 5m ladder of mass 12kg rests against a wall with its base 3m from the wall. A painter of mass 55kg sits 3.5m of the way up the ladder. what is the horizontal force in N exerted on the ladder by the wall? a)110.45 b)178.45 c)232.67 d)327.08


in the previous problem what is the magnitude in N of the vertical force exerted on the ladder by the ground? a)656.6 b)117.6 c)539 d)345.67



i tried to solve this problem by adding the masses of the ladder and the painter and then multiplying it by the height and gravity and trying to resolve the vector for the x direction. but i think i am missing a step or just not doing it right; i am studying for a test next week so this is a prob from the test bank

i would appreciate any help on this cause it will b on my test

thnx

ty
 
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You are right to resolve the force into x and y components.
Work out where the center of mass is.
 
i found the center of mass

but i am not sure how to incorporate that into the problem

and then how i can resolve the vectors

pls help
 
Draw a diagram.
 
What forces are acting on the ladder? In what directions? Since the system is in equilibrium, they must all be equal.
 
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