Choke

 Choke coil

The choke coil works because it acts as an inductor. When the current passing through changes, as AC currents do, it typically creates a magnetic field in the coil that works against that current. This property, known as inductance, blocks most of the AC current from passing through.

Inductor

 The inductor is a component that allows DC, but not AC, to flow through it

Choke with starter is used in fluorescent tubelight

Filter circuit

 Filter circuit 

If the surge exceeds the normal ±180 volt peak dynamic range of the power wave, the dynamic clamp circuit (D1 C3) which tracks the peak of the power wave comes into play

Placing a diode in reverse bias in parallel to the load eliminates voltage spikes by going into conduction before a large voltage can form across the motor. And this is how a DC transientvoltage

 suppressor circuit works to eliminate 

harmful voltage spikes.

The filter circuit is used in spike

 guard to filter out the power spikes and  protect against power surges

Capacitor 

A

The capacitor allowsalternating current (AC) to pass but it blocks direct current (DC). 

Tricks

 

 

Bimetallic strip

A bimetallic strip is used to convert a temperature change into mechanical displacement. The strip consists of two strips of different metals which expand at different rates as they are heated, usually steel and copper, or in some cases steel and brass. The different expansions force the flat strip to bend one way if heated, and in the opposite direction if cooled below its initial temperature. The metal with the higher coefficient of thermal expansion is on the outer side of the curve when the strip is heated and on the inner side when cooled.

The bimetallic strip is used in emergency switch

Remote sensing and Satellite imaging

Remote sensing
Is the acquisition of information about an object or phenomenon  without making physical contact with the object and thus in contrast to on-site observation. Remote sensing Is used in numerous fields including geography land surveying and most Earth science disciplines for e.g. hydrology, ecology, oceanography, glaciology and geology (detecting ores)

Satellite imaging
or space borne photography are images  of earth or other planets collected by imaging satellites. Images can be in visible colors and in other spectra. There are also elevation or topographical maps usually made by radar images. Interpretation and analysis of satellite imaging is conducted using specialized remote sensing applications
The em waves consist of both electric and magnetic field waves. These waves oscillate in perpendicular planes with respect to each other and are in phase.
The 7 types of em waves are radio,microwave , infrared, visible light, ultraviolet,x-rays,gamma rays.
Metals reflect radio waves.
Upon reflection if the collision is inelastic the speed of the em wave changes. Since the speed is dependant upon the frequency, the frequency tuning is necessary.
The energy density is directly proportional to the square of the amplitude of the electric or magnetic field The amplitude changes with respect to the material through which it is propagating. There may be need of amplitude tuning.
Factors affecting the propagation of em waves
Reflection
Refraction
Scattering
Dispersion
Interference
Height of antenna
Polarization
Magnetic field 

HTML Goodies

HTML offers a whole new set of goodies for your website...
Let me tell you more about this ...

The new HTML elements come with inbuilt validation.

The bootstrap offers wide range of latest templates to choose from.

The jumbotron indicates a big box for calling extra attention to some special content or information.A jumbotron is displayed as a grey box with rounded corners. It also enlarges the font sizes of the text inside it.

Example

Hello, world!

This is a simple hero unit, a simple jumbotron-style component for calling extra attention to featured content or information.

---

It uses utility classes for typography and spacing to space content out within the larger container.

Learn more

A progress bar can be used to show a user how far along he/she is in a process.

A progress bar with a label looks like this:

70%

Bootstrap provides several types of progress bars including animated one.

If you have a web site with lots of pages, you may wish to add some sort of pagination to each page. 

A basic pagination in Bootstrap looks like this:

• 1
• 2
• 3
• 4
• 5

Pager is also a form of pagination that provides previous and next buttons (links).

The Carousel plugin is a component for cycling through elements, like a carousel (slideshow).

The Modal plugin is a dialog box/popup window that is displayed on top of the current page:

The Popover plugin is similar to tooltips; it is a pop-up box that appears when the user clicks on an element. The difference is that the popover can contain much more content.

 

The Scrollspy plugin is used to automatically update links in a navigation list based on scroll position.

Wish you a great time constructing your website ...

Green House Effect

The greenhouse effect

The exchange of incoming and outgoing radiation that warms the Earth is often referred to as the greenhouse effect because a greenhouse works in much the same way.

Incoming UV radiation easily passes through the glass walls of a greenhouse and is absorbed by the plants and hard surfaces inside. Weaker IR radiation, however, has difficulty passing through the glass walls and is trapped inside, thus warming the greenhouse. This effect lets tropical plants thrive inside a greenhouse, even during a cold winter.

A similar phenomenon takes place in a car parked outside on a cold, sunny day. Incoming solar radiation warms the car's interior, but outgoing thermal radiation is trapped inside the car's closed windows.

Water vapor, CO2, methane, nitrous oxide (N2O)  and other greenhouse gases act like a blanket, absorbing IR radiation and preventing it from escaping into outer space. The net effect is the gradual heating of Earth's atmosphere and surface, a process known as global warming.

The ozone layer is a belt of the naturally occurring gas "ozone." 

Today, there is widespread concern that the ozone layer is deteriorating due to the release of pollution containing the chemicals chlorine and bromine. Such deterioration allows large amounts of ultraviolet B rays to reach Earth, which can cause skin cancer and cataracts in humans and harm animals as well.

...It is time to reduce pollution to reduce the green house effect...
Measures to reduce poisonous gases:
Water Vapor: Dehumidifiers
CO2:Planting trees
N2O:filters in traffic emission
Methane:reduce oil spills
Chloroflorocarbons:reduce CFC in Refrigerator and air coolers