2. WORKING OF REMOTE CONTROL
You may already know something about the EM (electromagnetic) spectrum.
The light we see is part of the EM spectrum. Radio waves, microwaves, and Xrays are part of it, too. Another part is called infrared. Like all parts of the EM
spectrum, infrared is a kind of energy that moves in waves. Our eyes can't see
infrared waves. We can't see radio, microwaves, or X-rays, either. Infrared waves
act in the same ways that light does. Infrared is reflected, or bounces off, light
things better than dark things. It is absorbed by dark things better than by light
things. Light travels in a straight line and so do infrared waves.
Your TV remote
sends out a beam of infrared waves. It sends out different
codes for different commands. The TV set receives the beam. A microchip inside
the TV "reads" the beam, much like your brain "reads" the signals sent to it by
your eyes. The microchip tells the TV what you want it to do. The remote can tell
it to turn the volume up or down. The remote can tell your TV to change
channels.
3. you may already know something about the EM (electromagnetic) spectrum.
The light we see is part of the EM spectrum. Radio waves, microwaves, and Xrays are part of it, too. Another part is called infrared. Like all parts of the EM
spectrum, infrared is a kind of energy that moves in waves. Our eyes can't see
infrared waves. We can't see radio, microwaves, or X-rays, either. Infrared waves
act in the same ways that light does. Infrared is reflected, or bounces off, light
things better than dark things. It is absorbed by dark things better than by light
things. Light travels in a straight line and so do infrared waves.
Remotes can send messages to your TV in a straight line. You can't use the
remote in another room and get the TV to do what you want. You can't stand
between a person using the remote and the TV. You must point the remote at the
TV and not be too far away, and you must not block the infrared beam.
4. So operate your remote control and enjoy watching
television …………………
5. How do calculator work
We all
know that calculators are these fast little machines that can do
calculations in incredible speed and have served to make humanity more
computationally exact species, but exactly, how do they
work? Well, whether you're talking about a scientific, financial
graphing, or even a calculator on your phone, they all work in a similar
fashion. In a nutshell, calculators just like their big brother, the
computer, work by understanding everything in terms of two states. We
call this binary and specifically, those two states are given as either a zero
or a one.
So, when we press buttons on a calculator, those buttons are connected to sensors
that send electrical currents to the integrated circuitry of a calculator. This circuitry
contains transistors that build up a logical framework for solving any given
calculation, and the more transistors present, the more advance the functionality of
the calculator is likely to
6. Transistors use
electricity to be in an on-state indicated by a one and off, indicated
by a zero. So when a calculator wants to add two numbers it first converts those
numbers into binary. For example, a four would be represented as 1-0-0 and a two
would be represented as 1-0. From there, the process of addition is dictated by each
column either summing to 0, 1, or two 1s, in which case a one would go into the
next column since calculators cannot comprehend a 2. Once the calculator has the
answer since it is in binary, it turns on a series of lines and/or pixels to create the
visual match of the number that we understand which is decimal or as
mathematicians call it - base 10.
Part of the reason why calculators are so quick is because at their core, they're
relying on electrical impulses which travel at the speed of light.
7. Working of a digital camera
The box remains the same as a film camera. Instead of the film, there is a
semiconductor chip, with an open sensitive surface, onto which the picture is
focused by the lens. This is commonly a Charge Coupled Device (CCD).
The chip is made up of a grid of photo sensitive pixels, the electrons are knocked off
by the light, in varying degrees and leave a charge in that area.
A computer, built within the camera, can access each of the pixels, assigns a
digital value, depending on the amount of charge (light) and then write this value to
a file, which is then stored in non-volatile memory.
Some cameras have internal memory and others (commonly) have a removable
memory card.
The picture files can then be accessed by a cable, or removing the memory card.
Once downloaded onto another computer or printer, the pictures can then be printed
using ink jet or laser printers, onto normal or glossy paper.
9. Working of a radio:
Radio is the transmission of signals by modulation of electromagnetic waves
with frequencies below those of visible light. At the radio studio, the sound waves
of a program go into a microphone that has electrical current running through it.
These sound waves create vibrations in the current as they travel through wires to
a control room. There, technicians control their volume and send them out
through a transmitter. An antenna on the transmitter sends these electrical waves
out through the air as radio waves. Radio waves travel through space in all
directions, just as waves of water spread out when a pebble is dropped into it
10. Working of a electric fan
An
electric fan is an electric motor with some fan blades attached to its rotating
shaft. As the motor spins, the fan blades rotate. Each blade is angled a bit, and as the
inclined plane of the blade moves through the air, it forces the air ahead of it forward.
Each blade does this on a continuous basis, and the result is a moving air stream. The
fan is taking air from the area behind itself and blowing it out the front. The fan
generates a movement of air, causing the warm, less dense air to rise, and the
cool, dense air to descend, thus creating a feeling of coolness in the air
