RRB ALP CBT II Basic Sciences & Engineering Notes on Simple Machines

The Railway Recruitment Board (RRB) conducts the RRB ALP exam to hire Assistant Loco Pilots. This is a regular exam used by the Indian Railways to hire Assistant Loco Pilots in various units around the country. The selection process includes CBT I, CBT 2, and CBAT stages. The CBT 2 has questions based on Basic Science. One of the topics for the same is Simple Machine. The notes for the same are given here.

Introduction to ALP CBT II Basic Sciences

A machine is a tool that consists of one or more pieces that use energy to carry out a certain task. Machines are frequently motorized and powered by mechanical, chemical, thermal, or electrical processes. To be classified as a machine, a power tool had to have moving parts in the past. However, the development of power tools without moving parts has been aided by the introduction of electronics.

Find the RRB ALP Syllabus and Exam Pattern here!

ALP CBT II Basic Sciences – Simple Machine

• Simple machine is a device with few or no moving parts that are used to modify motion and force to perform work.
• Simple machines have only one or two parts, they don’t have motors and they make work easier for people by changing the direction or the size of a force applied to it.
• A hammer is a machine. Work is done on the handle, which in turn does work on the head of the mail, which does work on a nail.
• There are simple machines and complex machines. Levers, punching machines, crowbars, bottle openers, etc. are examples of simple machines while motorcycles, trucks, cars, etc. are some examples of complex machines.

Check the RRB ALP Eligibility Criteria here!

ALP CBT II Basic Sciences- Six Types of Simple Machines

The assistant loco pilot stage two of the computer-based exam of RRB has two topics, they are basic sciences and engineering. The Six Types of Simple Machines in these are mentioned below - 

1. Levers
2. Screw Jack
3. Wheel and axle
4. Pulleys
5. Inclined plane
6. Wedge

Lever

• Lever is a type of simple machine that is used to lift heavy loads. It is a rigid bar that moves about a fixed point, a fulcrum.
• Example: Cutting plier, A pair of scissors, Crowbar, Beam balance, Hand pump.
• It consists of three parts: Effort, Fulcrum and Load.
• The distance of the load from the fulcrum is called the load arm. The distance of the effort from the fulcrum is called the effort arm.

Wheel and Axle

• A wheel and axle is a wheel with a rod in it that is called an axle and it is used to lift, and move loads or rotate through the central power.
• Examples of a wheel & axle can be found on any bicycle tire as well as a simple rolling pin.

Screw

• A screw is an inclined plane wrapped around a nail. It consists of circular edges called thread.
• The effort is applied to the head of the screw.
• Example: Screw, Jackscrew, etc.

Pulley

A pulley is a simple machine used for lifting goods. It consists of a small wheel made of metal or wood with a groove cut on its circumference. A light rope passes over the grooved rim. It can rotate about an axle passing through its centre. The axle of the pulley is supported on a frame known as the block. The load is attached to one end of the rope which passes over the pulley and the effort is applied at the other end. The effort applied is equal to the load to be lifted.

Types of pulley

1. Fixed pulley: If the block of a pulley is fixed, then it is called a fixed pulley. The load is attached to one end of the rope and effort is applied at the other end. 
2. Movable pulley: If the block of a pulley is movable, then it is called a movable pulley. In a movable pulley, one end of the rope is attached to a fixed support and the other ends first pass through the movable pulley and then the fixed pulley. 

Inclined Plane

• It is a sloping surface or a wooden plank. It multiplies the applied effort. A sloping surface is called an inclined plane, from the following figure.
• BC – Horizontal plane, BA – Inclined plane
• The angle between the inclined and horizontal plane is known as the angle of inclination 

• By applying a suitable effort, a load can be raised on the slope or lowered down the slope of the plane.
• E.g.: A ladder, an escalator, a staircase

The principle of Inclined Plane

• The inclined plane is a slope. It is a basic mechanical device to lift a body to a certain height with less effort.
• To lift a body to a certain height, we have to apply a force on the body. Now in an inclined plane only pushing force parallel to the inclined plane is used.

Wedge

• A wedge is a triangular-shaped tool. A wedge consists of two or more sloping surfaces with one end sharp or pointed edge while the other one is a blunt edge.
• Examples: Axe, knife, nail, sickle, etc. 

We hope you liked the article on ALP CBT II Basic Sciences. For more such information related to previous year exams, notes, sample papers etc, download the Testbook App Today.