Question

The figure shows a mechanical set-up. What mechanism is reflected by this schematic?

(A) Sliding mechanism
(B) Rotating mechanism
(C) Slider-crank mechanism
(D) Rolling mechanism

Answer 1

Hint : In order to find the correct answer for the above question, first of all we will try and understand the schematic diagram provided to us. We will then find out the moving parts in the above circuit and then compare it with the different kinds of mechanisms used in machines to identify the mechanism. Finally, we will discuss the identified mechanism.

Complete Step By Step Answer:
As, we can see from the given figure, the assembly of a piston, cylinder, connecting-rod and crankshaft is a classic type of the slider-crank mechanism. Generally a slider crank transmits motion generated by the linear displacement of the piston by a working fluid to rotational motion of a shaft.
There are many applications of slider cranks and among them, most common are engines. The utilization of those mechanisms for power generation began with the external-combustion engine within the late 18th century and has developed into possibly its most recognizable form because of the current day combustion engine. One piston engine model could function a functional, eye-catching example of a slider-crank.
Slider-crank mechanism, arrangement of mechanical parts designed to convert straight-line motion to rotation, as during a reciprocating piston engine, or to convert rotation to straight-line motion, as during a reciprocating piston pump. The essential nature of the mechanism and therefore the relative motion of the parts can best be described with the help of the accompanying figure, during which the moving parts are lightly shaded. The darkly shaded part $1$ , the fixed frame or block of the pump or engine, contains a cylinder, depicted in cross section by its walls $DE$ and $FG$ , during which the piston, part $4$ , slides back and forth. The tiny circle at $A$ represents the most crankshaft bearing, which is additionally part $1$ . The crankshaft, part $2$ , is shown as a straight member extending from the most bearing at $A$ to the crankpin bearing at $B$ , which connects it to the rod, part $3$ . The rod is shown as a straight member extending from the crankpin bearing at $B$ to the wrist pin bearing at $C$ , which connects it to the piston, part $4$ , which is shown as a rectangle. The three bearings shown as circles at $A$ , $B$ , and $C$ permit the connected members to rotate freely with reference to each other.
The trail of $B$ may be a circle of radius $AB$ ; when $B$ is at point h the piston is going to be in position $H$ , and when $B$ is at point $J$ the piston is going to be in position $J$ . On an internal-combustion engine, the top end of the cylinder (where the explosion of the gasoline-air mixture takes place) is at $EG$ ; the pressure produced by the explosion will push the piston from position H to position $J$ ; return motion from $J$ to $H$ would require the rotational energy of a flywheel attached to the crankshaft and rotating a few bearing collinear with bearing $A$ . On a reciprocating piston pump the crankshaft would be driven by a motor.
Therefore, the answer to our question is option (C) i.e., the slider crank mechanism.

Note :
Here, it is to note that the figure shows two components that are moving or rotating. The first is the part $A$ which is rotating and the part $C$ that is sliding linearly, and hence we could consider a system consisting of both of these motions which is similar to the slider-crank mechanism.