A gardener attempts to drag a bag of soil across a concrete patio by pulling on a…
PHYSICS · Multi-part · CBSE · Physics · Laws of Motion · Laws of Motion
Problem
A gardener attempts to drag a 40kg bag of soil across a concrete patio by pulling on a rope that makes an angle of 25∘ above the horizontal. The coefficient of static friction between the bag and the patio is 0.50.
Respond to each part, showing complete algebraic work and including appropriate units.
(a) Construct a free-body diagram for the bag while it is still at rest but the gardener is pulling on it.
(b) Express the normal force on the bag in terms of the unknown pulling force F and the given quantities.
(c) Using your expression from part (b), derive an equation for the minimum magnitude Fmin of the pulling force required to make the bag just start to slide.
(d) Evaluate Fmin numerically, and then compare it to the minimum horizontal force that would be required if the rope were held perfectly horizontal. Explain the physical significance of any difference in the two results.