Question

Suppose that you can lift no more than 650 N (around 150 lb) unaided. (a) How much can you lift using a 1.4-m-long wheelbarrow that weighs 80.0 N and whose center of gravity is 0.50 m from the center of the wheel.

Answer 1

Wl = 1740 N

Step-by-step explanation:

maximum lift weight unaided = force exerted (F) = 650 N

length of the wheelbarrow (L) = 1.4 m

weight of the wheelbarrow (w) = 80 N

distance of center of gravity of the wheel barrow from the wheel = 0.5 m

distance of center of gravity of the load from the wheel = 0.5 m

find the weight of the load (Wl)

from the diagram attached we can see that there is going to be a rotation about the axis A. let clockwise rotation be positive

ΣT = (F x 1.4) - ((Wl x 0.5) + (w x 0.5) = 0

(F x 1.4) = ((Wl x 0.5) + (w x 0.5)

Wl =
`((F x 1.4) - (w x 0.5))/(0.5)`

Wl =
`((650 x 1.4) - (80 x 0.5))/(0.5)`

Wl = 1740 N