# physics

posted by
**sand**
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A ladder of length 5m has mass of 25 Kg. the ladder is leaned against a frictionless vertical wall at an angle of 100 with the vertical. A repairman with a mass of 82Kg needs to stand on an upper rung of the ladder that is 1m from the end. What is the minimum coefficient of friction between the ladder and the floor such that the ladder doesnâ€™t slip?