What is the mechanical advantage of a pencil sharpener made from a wheel and axle with a mechanical advantage of 3 and a wedge with a mechanical advantage of 4?

3×4= 12

Explanation:

Mechanical Advantage( M.A.) in a simple machine is defined as the ratio of the force that performs the useful work of a machine to the force that is applied to the machine.

Mechanical Advantage of Compound Machine = Product of mechanical advantages of the simple machines that it consists of, that is the mechanical advantage of wheel and axle multipled by the mechanical advantage of wedge.

Therefore,

M.A. wheel and axle = 3

M.A. wedge= 4

M.A. pencil sharpener= 12

Note: Mechanical Advantage has no unit.

weight of the box is given as

here this is placed on the inclined of angle 42 degree

now this weight will have two components one is along the incline other is perpendicular to it

so here we need to apply a force parallel to incline opposite to its component of weight

so here the component of weight is given as

here we have

so it requires 75 n force to move it upwards