wedge (redirected from wedge shape)

wedge, piece of wood or metal thick at one end and sloping to a thin edge at the other; an application of the inclined plane. It is employed in separating two objects from each other or in separating one part of a solid object from an adjoining part, as in splitting wood. The thin edge is applied to the surface of the solid or to the crack between two solids, and force is applied to the opposite thick edge. The ax, chisel, knife, nail, and carpenter's plane are wedges, and the cam is a rotating wedge.

---

wedge

In mechanics, a device that tapers to a thin edge, usually made of metal or wood, and used for splitting, lifting, or tightening, such as to secure a hammer head onto its handle. The wedge is considered one of the five simple machines. Wedges have been used since prehistoric times to split logs and rocks; for rocks, wooden wedges, caused to swell by wetting, have been used. In terms of its mechanical function, the screw may be thought of as a wedge wrapped around a cylinder.

---

wedge

1. Golf a club with a face angle of more than 50°, used for bunker shots (sand wedge) or pitch shots (pitching wedge)

2. a wedge-shaped extension of the high pressure area of an anticyclone, narrower than a ridge

3. Mountaineering a wedge-shaped device, formerly of wood, now usually of hollow steel, for hammering into a crack to provide an anchor point

4. any of the triangular characters used in cuneiform writing

5. Photog a strip of glass coated in such a way that it is clear at one end but becomes progressively more opaque towards the other end: used in making measurements of transmission density

---

wedge [wej]

(communications)

A convergent pattern of equally spaced black and white lines, used in a television test pattern to indicate resolution.

(design engineering)

A piece of resistant material whose two major surfaces make an acute angle.

(electromagnetism)

A waveguide termination consisting of a tapered length of dissipative material introduced into the guide, such as carbon.

(engineering)

In ultrasonic testing, a device which directs waves of ultrasonic energy into the test piece at an angle.

(mathematics)

A polyhedron whose base is a rectangle and whose lateral faces consist of two equilateral triangles and two trapezoids.

(meteorology)

ridge

(optics)

An optical filter in which the transmission decreases continuously or in steps from one end to the other.

A refracting prism of very small angle, inserted in an optical train to introduce a bend in the ray path.

---

Wedge

A piece of resistant material whose two major surfaces make an acute angle. It is closely related to the inclined plane and is used to multiply the applied force and to change the direction in which it acts (see illustration).

Force F is the smaller applied force and Q is the larger force to be exerted. In the absence of friction, forces must act normal to their surfaces; thus the actual force on the inclined surface is not Q but a larger force F_n. Summing up forces in the horizontal and vertical directions gives Eqs. (1). (1) 

Combining the expressions for F and Q and solving for F gives Eq. (2).

(2) 

If angle Θ is small, the reaction of Q against F is exceeded by the friction between the face of the wedge and the adjacent body on which it rests. Thus the wedge tends to remain in position even when loaded by a large force Q. See Simple machine