7 months ago

## Perpetual Motion Machine (PMM)

Any device which violates first law or second law of thermodynamics is called a perpetual motion machine (PMM). These devices operate under the principle of sustained ..

1 year ago

## Fundamental Concepts and Terms in Vibration

Vibration is a mechanical phenomenon, It is a movement first in one direction and then back again in the reverse direction. e.g: the motion of a swinging pendulum, ..

1 year ago

## Throw-away-tipped Turning Tool

Whenever the tool is not performing a machining operation satisfactorily, it is assumed that the tool has been failed. Normally when the tool fails the tool will ..

• 2 years ago

## Differences between Drop Forging and Press Forging

Drop Forging: It utilizes a closed impression die to obtain the desired shape of the component. The shaping is done by the repeated hammering given to the material ..

• 2 years ago

## Parallel-Axis Theorem

Consider the moment of inertia IAA’ of an area A with respect to an axis AA’ (Fig.). Denoting by y the distance from an element of area dA to AA’, ..

3 years ago

## Safety Measures while Working with Electrical Machines

When operating with electrical machines, operator or user for the first time should be careful to avoid accidents. Based on the experience of many experts, some ..

• 3 years ago

## Comparison between Conductors, Semiconductors and Insulators

Comparison between Conductors, Semiconductors and Insulators can be done in aspects like conductivity variation, conductivity order, electrical resistivity, temperature ..

3 years ago

## Theories of Fatigue

There are many theories of fatigue; we have written in brief about the three theories – Orowan theory, fatigue limit theory and wood’s theory here. (i) Orowan ..

• 3 years ago

## Definition of Mass and Weight

Sometimes much confusion and misunderstanding are created while using the various systems of units in the measurements of force and mass. This happens because of the lack ..

• 3 years ago

## Fuel Cells: What are They and How do They Work ?

There are many people who believe that much of the power generation of the future will be through the use of fuel cells. They are already being used in various capacities, ..

4 years ago

## Thermometer

Any body with at least one measurable property that changes as temperature changes can be used as a thermometer. Such a feature is called a thermometric property. ..

4 years ago

## Three Thermal Science Disciplines

Thermal systems engineering typically requires the use of three thermal science disciplines: Thermodynamics, Fluid mechanics, and Heat transfer. Figure 1 shows the roles ..

• 4 years ago

## Comparison of Petrol with Liquefied Petroleum Gas (LPG)

Comparison of Petrol with Liquefied Petroleum Gas (LPG) can be done in aspects like fuel consumption amount, octane rating, fuel odor, spark plug life by using fuel, ..

4 years ago

## General Characteristics for Selection of Measuring Instruments

Various specific terms describe the characteristics and quality of measuring instruments, defined as follows: Accuracy: The degree of agreement of the measured dimension ..