WEDGE

Wedge is also a type of simple machines. It is used in levers as a fulcrum. It is also used for splitting the wood in to small pieces. It is used as an Ax.

CONSTRUCTION OF WEDGE: -

A wedge is made of two inclined planes joined together. The effort ‘P’ is applied on the top of the wedge placed over a wood log. The wedge enters the wood and splits it. The reaction forces R1 & R2 are acting perpendicular on the inclined planes of the wedge. These forces and resultant frictional forces are responsible for keeping the wedge inside the wood firmly.

MECHANICAL ADVANTAGE OF WEDGE: -

Let us consider that the wedge is in equilibrium under the action of forces three forces R₁, P and R₂ and neglecting frictional forces. According to figure below the forces P, R₁ and R₂ are represented by the sides of D XYZ such that effort P the reaction R₁ and R₂ are represented by XY, YZ, and ZX which are the sides of, D XYZ respectively.

Mechanical Advantage (M.A). = load/effort

For equal sides of wedge i.e. = R₁ = R₂ = R

M.A. = R/P

M.A = ZX/XY

Triangle ABC and triangle XYZ are similar, therefore,

ZX=AC and XY=BC

M.A. = AC/BC

Mechanical advantage = length of inclined surface of wedge/thickness of wedge

From above expression it is clear that if the thickness of the wedge is decreased the mechanical advantage of the wedge will increase & if the wedge is more sharper, then the mechanical advantage will increase.