A ladder leen again a perfectly smooth vertical wall at angle of 30 to the horizontal.,
A load of 800N placed 3/4 of the way up, the ladder if the ladder rest at a rough horizontal surfaces which prellent shipping. Find the magnitude and direction of the reaction between the ladder and the ground.
The total force at the ground,
"N_g=400+800=1200(N)"
The reaction at the wall,
"\\Sigma M_{gr}=0:-R\\cdot l\\sin30\u00b0+800\\cdot\\frac{1}{4}l\\cos30\u00b0+400\\cdot \\frac{1}{2}l\\cos30\u00b0=0"
"R\\cdot l\\sin30\u00b0=800\\cdot\\frac{1}{4}l\\cos30\u00b0+400\\cdot \\frac{1}{2}l\\cos30\u00b0"
"R=\\frac{800\\cdot\\frac{1}{4}\\cos30\u00b0+400\\cdot \\frac{1}{2}\\cos30\u00b0}{\\sin30\u00b0}=693(N)"
Comments
Leave a comment