Question

*********Note: Do this entire problem numerically. Do not calculate the masses of any object in the problem. The final answer should come out nicely.

Show all work and formulas!

A painter wants to paint the upper portion of a building and uses a uniform ladder.

• Painter weighs 1000 N
• Ladder is 4.25 meters and weighs 150 N
• Base of ladder to the wall is 2 meters
• Ladder leans on wall at an angle of 61.928 degrees
• Coefficient of friction against the ground is .6
• Coefficient of friction against the wall is .25

1. How high can the painter climb without the ladder slipping?
2. Draw a detailed picture labeling all 6 forces.
3. Set up the 5 equations used with the 5 unknown variables
4. The final answer may be usual, explain in words why that is.

Answer 1

The painter can climb up to a distance of 1.678 m on the ladder.

The answer suggests that the painter can't climb half the ladder safely, he have to stay below the center of mass of the ladder otherwise he/she would topple. Friction would fail to provide supports.