Sleep. You remember that? It was that lovely revitalising thing we all used to do every night. Pfft! Not any longer.
It seems these days everyone I speak to, from family members to friends, is suffering from some sleeping disorder or another. If it isn’t problems falling to sleep, it’s frequent waking and in some cases full blown insomnia. Eek! Continue reading “How Electronic Devices Affect Sleep Quality”
Science is a systematic approach that collects and builds knowledge. Likewise, they are many scientific discoveries happening in every part of the world. But there are amazing and outstanding discoveries and inventions made in recent times that are incredible. Some are listed below:
Continue reading “10 Interesting Science Discoveries”
Today we proudly announce the First WinnerScience Innovative Idea Contest- 2015 (WIIC-2015).
The objective of the WIIC is to encourage the students to solve the daily life problems with easy and innovative methods. The aim of the contest is to get the idea from your side, the idea may be in the idea form only or it may be in the practical form also. The proposal should focus on to solve the problems and it may be related to any field of science. Continue reading “WinnerScience Innovative Idea Contest -2015 (WIIC-2015)”
Definition of cathode rays:
Cathode rays are the group of fast moving negatively charged particles. These negatively charged particles are electrons. These rays are shot out at a high speed from the cathode of a discharge tube at a pressure below 0.01 mm of mercury.
15 Properties of Cathode rays:
1. Cathode rays travel in straight lines.
2. These rays are deflected by electric field. This is obvious because these rays are nothing but electrons.
3. These rays travel normally from the surface of cathode. Continue reading “Cathode rays and their 15 properties”
As recording process in holography is based on the principle of interference. For recording and for sustained interference, the path difference between various interfering light waves should always be less than longitudinal coherence length. For ordinary light source like mercury the coherence length is very small (≈3cm). The path difference introduced between light waves reflected from different points of object can be much more than this value. Thus interference pattern cannot be recorded. While coherence length for laser source can be as high as 600 km. As a result, sustained interference pattern will be recorded on hologram. Thus hologram cannot be made without laser source. Continue reading “Why laser is needed in holography”
Reflection hologram: If recording material in hologram is placed such that reference beam and object beam approach it from two opposite sides, then hologram formed is called Reflection Type hologram. The interference fringes are usually parallel to the surfaces of recording medium. When such a hologram reconstructed, then reference beam and object beam lie on the same side of hologram. Continue reading “Reflection and transmission hologram”
DEFINITION TRANSVERSE ELECTRIC (TE) WAVES OR H WAVES IN PARALLEL PLANES:
In the case, the component of electric field vector E lies in the plane transverse to the direction of propagation that is there is no component of E along the direction of propagation where as a component of magnetic field vector H lies along the direction of propagation.
Derivation of transverse electric waves in parallel planes:
As the direction of propagation is assumed as z-direction, therefore
Ez = 0 and Hz is not equal to 0
Now by substituting Ez = 0 in equation (8) of article “waves between parallel planes”, we get
Ex= 0 and Hy = 0 and
Ey not equals to 0 , Hx not equals to 0
Now write wave equations for free space in terms of E
= -w2μεE (because g2g = (jwμ) (σ + jwε) As σ =0(from assumption (c) of article “waves between parallel planes” => g2g =-w2με)
Or d2E/dx2 + d2E/dy2 + d2E/dz2 = -w2μεE
For the y component, the wave equation will become Continue reading “Transverse electric waves”
Work: In physics work is said to be done when a force acting on a body displaces it through a certain distance. The work by a constant force is measured by the dot product of force will displacement.
i.e. W = F.S or W = F S cosq …(1)
where F = force and S = displacement
And q = angle between F and S.
From eq.(1), we have W=F cosq x S. Therefore, work done by a force is equal to the product of the component of the force in the direction of displacement of the body and the distance through which the body moves. Continue reading “Work and its types”
Now a days lots of result is done in the field of energy science. Energy science may include biodiesel, solar energy and other many energy resources. I have compiled the list of best or top 20 journals of energy science. If you are researcher in this field you can search these journals and try to contribute their articles for the same. The ranking is done on the basis of impact factor of journals. Continue reading “Best journals of Energy of 2011”
Cosmology is a science related with the space. It can be divided into two parts. one is the physical cosmology and other is the modern cosmology. Physical cosmology deals with the origin, evolution and future of the universe. There are various cosmological events which can affect the earth. The events like speed bump, black hole, asteroids ( a large one) and supernova can affect the life on earth.
Supernova is a stellar explosion, can result in a burst of explosion and can outshine the entire galaxy. During a small interval supernova supernova is expected to radiate a large amount of energy which is equal to energy radiated by the sun in his whole life.
Literally black hole means where gravity prevents anything to escape even the light. It is called black because it reflects nothing.
This cosmological events can definitely affect the earth. If you know more events, then please share with us.
Note: This article is originally contributed by Paul Taylor and edited by the team of winnerscience.com