Question

A block moves up a 30 degree incline under the action of three applied forces. F1 is horizontal and of magnitude 40 N. F2 is normal to the plane of the incline and has magnitude of 20 N. F3 is parallel to the plane and of magnitude 30 N. Determine the work done by the forces as the block (and point of application of each force) moves 80 cm up the incline. (answer in J)

Answer 1

Answer

given,

F₁ is horizontal = 40 N

F₂ is normal = 20 N

F₃ is parallel = 30 N

work done by

W₂ = 0 as force is acting perpendicular to the direction of motion.

as the motion moved to 0.8 cm

W₃ = F₃ x d

W₃ = 30 x 0.8

W₃ = 24 J

W₁ = F₁ x d

W₁ = F₁ cos ∅ x d

W₁ = 40 cos 30⁰ x 0.8

W₁ = 27.21 J