Scalar Quantities Vs Vector Quantities

Physics involves measuring and predicting various quantities (or physical values) like force. mass. and velocity.These values can be classified into those having only magnitude and those having both magnitude and direction. A quantity that has magnitude without a direc­ tion is referred to as a sea/or quantity. Mass is a scalar quantity. Energy and work are also scalar quantities.

On the other hand. force is a value with a direction. You can see that from the fact that the motion of an object changes if you apply force from a different direction.

A quantity that has a direction is called a vector. Velocity and acceleration and momentum are also vector quantities, as they have direction. You may forget the terms scalar and vector, but you should keep in mind that there are two types of values in physics:

1. Those with just a magnitude 
2. Those with both a magnitude and a direction

Vector: Basics

A vector is represented using an arrow.The length of the arrow represents the magnitude of the vector. and the point represents its orientation. or direction.Two vectors with the same magnitude and direction are equivalent to one another. even if they do not have the same origin.

 

Also note that the magnitude of a vector (represented by the length of the arrow) can be noted with absolute value symbols, like |a| or simply as a.

The sum of two vectors (a + b) is shown by joining the head of vector a to the tail of vector b. and then extending a line from the tail of a to the head of b, as shown in the figure. As this vector is a diagonal of the parallelogram in the figure, it is obvious that it is also equivalent to b + a. Therefore, we know that the following is true:  

Commmunitative Law: a + b = b + a

 

Negative Vector

Vector -a or a preceded by a minus sign, yields a sum of zero when added to Vector a. In an equation, the relationship looks like this: a + (-a) = 0

In terms of geometry, Vector -a is simply vector of the same magnitude as Vector a, but in the exact opposite direction. The 0 on the right side of this equation represents zero as a vector, referred to as a zero vector. When vectors cancel each other out in this way. an object is said to be in equilibrium.

 

Difference between Two Vectors

The difference between two vectors (a - b) can be defined as follows:

Commmunitative Law: a - b = a + (-b)

Thus, we can find the result of the equation using the same process for summing vectors:

 

Multiplying Vectors By Scalars

Doubling vector -a means doubling its magnitude without changing its direction. The result is represented as 2a.

Generally, k multiplied by a (k.a) represents vector with magnitude k times greater than a but in the same direction.

nb: this is a nostalgic note of mine from a book Manga Guide to Physics

It's Your Mood..! Let's See how We Can Manage it

What you'll receive from life heavily relied on  your effort, and your emotional states aka moods. By the time you are in a positive mood, everything just seem perfect - you can be more productive, doing an effective multi-tasking, and any obstacle you face just feels like nothing. But when you are in a bad mood, you tend to perceive much of everything in negative ways - even a barking dog can turns you into a grumpy cat.  So, most people will agree if I say that mood gives a significant effects on your daily life.

So, if such a thing gives a significant impact to our life, how can we control it? How can we stabilized our emotional states? Many people think that mood is created by external events. When things go as your positive expectation, you are in a good mood, but when things go awfully unexpected  you're going to be in a bad mood, right?

Actually, the statement is neither a valid argument, nor fact. Robert Thayer, a psychologist and the author of Calm Energy, said that mood develops from internal events rather than external events. Robert also said that  

Events are random. Even if you try to plot them down in to a good looking chart, you will find that the correlation between an event and your emotional states is little to none.

Biofeedback At A Glance

In essence, biofeedback is an approach to work with tension/stress of which pertains supervising which aims to apply elective regulation over unconscious physical activities just like pulse rate, blood pressure level, skin conductance, and even muscular tension.

Image Sources: http://www.makingthemodernworld.org.uk

The basic concept is originated from animal testing (using laboratory rat) performed approximately five decades ago of which demonstrating that rats can adjust their own pulse rate if presented positive neurological stimulus each time their own heart beat accelerated or lowered. The approach that: "Thoroughly unconscious physical processes can get adjusted through controlled environment" was barely unique; Ivan Petrovich Pavlov had already shown this a long time ago, by monitoring and measuring salivation process of his own pet. Nevertheless, knowing the prospective healing utilization of the particular concept for stressed humans was completely new, thus, demanded cutting-edge devices, which leads to biofeedback technology that we know today.

Self-Esteem Based on Popular Psychology Perspective

While it is not really the same thing, self esteem is often considered as self confidence where both terms signify how an individual value and evaluate himself.

High self esteem indicated by positive perspective of self-assessment, while low self esteem indicated by negative perspective of self-assessment. It is believed that self esteem level is significantly impact our quality of life in many areas - with the assumption that the higher level of self-esteem we have, the better quality of life we get.


However, facts show us that it 'adjusts' perception rather than reality, and the majority belief (about self esteem) is mostly based around anecdotal evidence, not based on solid scientific studies

What Makes The Hype

Just like many kinds of pseudo science, the public interest is mainly driven by authorities. In 1986, California legislature gave enormous amount of money for the purpose of increasing self esteem level of California citizens. The authority believed that there are many California citizen that has low self esteem level, with assumption that low level of self esteem contributes to many social problem just like crime, welfare dependency, schoold failure etc.

Popular Myth: "We Only Use 10% Of Our Brain Capacity"

One of the most popular myth in science history is a statement that we only utilize 10% of our brain capacity. This myth makes most people to believe that there are 90% more capabilities that are still waited to be used. Just to mention a few, telepathy, super-human regeneration or even x-ray vision.

Even though this myth is often attributed to William James (the father of Americam psychology) and Albert Einstein, it's still unclear how this all begin. However, public were already aware of this myth in late 1930s. And just like many other pseudoscience, some authorative figures also helped the spread of this false information. During 1950s, this misleading informarion was widely (and wildly) used in many self improvement industries, even in some Dale Carnegie's works..!

10% brain capacity might be true if we're talking about Homer
Simpson who lives in The Simpson Universe

It could be very possible that this myth is triggered by misinterpretation on neurological studies conducted in 1930s. At that time, it was well-known that there are many researchers used electrical stimulation to figure out corelation between physical functions and brain cortex. When a certain area of animals' cortex is stimulated, a physical response will occur. This phenomenon also happens on human. However, there are wide area of brain cortex that don't induce physical/motoric reaction. At that time, researchers call those area as silent cortex, which possibly misinterpreted by the myth starter(s) as part of brain that are left unused or still not activated.

What Happen When Our Brain Gets Bigger?

Not only are the ‘laws of brain-size evolution’ consistent with massive modularity,but they also give the latter some independent support. Striedter (2004)reviews a wide range of comparative and evolutionary data, and is able to extract a number of robust generalizations about what happens to brains when their absolute size increases, within a certain lineage (see also Geary, 2005). One is that larger brains become significantly more modular in their organization. This is because, as the total number of neurons increases, the density of dendrite connectivity amongst neurons significantly decreases. (This is, no doubt, partly because of the energetic costs associated with building and maintaining neural connections—Aiello and Wheeler, 1995; and partly because of the constraints imposed by slow speeds of signal propagation within and between neurons.) The result is that neurons tend to maintain more of their local connections, while giving up a greater proportion of their long-distance ones, resulting in an architecture that appears significantly more modular.

Another (related) generalization described by Striedter (2004) is that an increase in the size in a given brain region tends to be accompanied by increases in functional differentiation amongst its sub-regions. And this generalization holds good, not only for local brain regions, but also for the brain as a whole.

In particular, the lateralization of brain functions increases as the overall size of the brain goes up, no doubt because of the costs of maintaining neural connections between the two hemispheres. What we should predict, then, as a result of the fourfold increase in brain size that occurred through the evolution of hominids, is that the brains (and presumably the minds) of humans became much more modular—containing many more functionally distinct processing systems—than the brains of our great-ape ancestors. Since I have previously argued the minds of apes and other non-human animals are already massively modular in organization, this is likely to mean that the transition to Homo sapiens will have seen the addition of many new mind / brain adaptations.

Should the resulting systems count as adaptations, however? Aren’t they rather side-effects of some general Bauplan governing increases in brain size? Initially, perhaps, some of them may have been. But exaptation is actually a form of adaptation. Where systems are shaped and maintained by natural selection they can count as adaptations, even if the processes through which they initially arose weren’t targeted on them in particular. (The penguin’s ‘wings’ are an adaptation for swimming, although they are exapted from limbs once designed for flight.) And such shaping and maintaining is likely to apply to most of the brain systems underlying the human mind, since cognition is just too important for survival and reproduction for it to be otherwise.

There is one other ‘law of brain evolution’ described by Striedter (2004) that is worth mentioning here. This is that as the size of one brain region increases relative to another, the extent of the neural projections from the larger to the smaller also increases. The result is that the relatively enlarged human neocortex has culminated in unusually extensive projections from the neocortex to the motor neurons in the medulla and spinal chord. This may give us a partial explanation of our species’ impressive abilities for fine-grained motor control, not only involving movements of the hands, but also the lips, tongue, and respiratory system necessary for the control of speech.

Migraine - All In Your Head

Pain from migraine headaches is typically
located on only one side of the head, behind the eye

The damage caused by headaches is eye-popping. About 45 million Americans suffer them regularly, and about half of the sufferers find the pain severe and sometimes disabling. The result: lost time from work, play, the day-to-day stuff of life. Count­ ing only the 30 million who suffer migraine headaches-one of the 150 described categories of headaches-American vic­ tims lose 157 million work days each year.

All In Your Head

Victims often describe the pain as throbbing or pound­ing. Other related symptoms include sensitivity to light, sound, and odor. Some expe­rience nausea, abdominal pain, or vomiting, and some sufferers report seeing auras or streaks of light shortly before the pain begins. Young victims may also complain of blurred vision, fever, dizziness, and upset stomach. A few children get migraines about once a month accompanied by vomiting; such headaches are sometimes referred to as abdominal migraines. About 5 percent of children younger than 15 report having had migraines, compared with 15 percent who experienced tension headaches.