Horror Movies are Good for You

by Anupum Pant

It is Halloween today and most of us must be busy making plans for the day. But if you’ve missed including a horror movie in your plans, after reading this post, you might want to consider putting it in the list.

Studies have shown that watching a horror movie can actually be beneficial to your health. In two separate experiments, scientists were able to record two different ways in which horror movies can be good for you. Of course, this shouldn’t encourage extremely sensitive people to force horror movies onto themselves. In spite of these proven benefits, pregnant women, old men, little kids and people with heart disorders must try to stay away.

Moreover, the benefits found, were not practically too big. So, if you are thinking of leaving your healthy diet plan and making up for it by starting to watch more horror movies, you are mistaken. But, scientifically, the discovery of such co-relations are considered as noteworthy.

The first study (increase in immunity)

Researchers suggest that while people watch horror movies, their brain secretes chemicals like dopamine, glutamate and serotonin. As a result, there is an increased brain activity, which makes the mind alert for a while. Additionally, threat signals that pass through the brain stimulate adrenal glands to produce adrenaline, which has an anesthesia like effect.

Secondly, a half-hour watch was found enough to boost the number of active white blood cells in their blood – they are responsible to keep diseases away. In the test, a first time watch of Texas Chainsaw Massacre by 32 men and women led to an increased immunity for some time. [Source Paper]

The second study (burns calories)

In another study conducted recently, scientists observed an average of 184 burnt calories among the people who watched The Shining (the 1980 thriller). Jaws took the second spot, with people burning on an average of 161 calories after watching it, and The Exorcist came third, with 158 calories. Top 5 calorie burning movies were as follows:

1. The Shining: 184 calories
2. Jaws: 161 calories
3. The Exorcist: 158 calories
4. Alien: 152 calories
5. Saw: 133 calories

Increased heart rate, muscular contractions, a surge in adrenalin, oxygen intake and greater carbon-dioxide output were the main reasons that  these extra calories got burnt. So, the next time you are watching a horror movie (working out), avoid popping popcorn. [Read more]

The Sun’s Unusual Behavior – Seen from Mercury

by Anupum Pant

The sun – as seen from Earth

For most of us living on Earth (closer to the equator), the sun has followed a simple path throughout the years. It rises, goes up at noon and then sets for rest of the day. It is a simple straight line for the complete year.
For people living a little away from the equator, things get a bit interesting. There, the summer sun at noon is overhead, but the winter sun is low at noon, not overhead. It isn’t very easy for a person living near the equator to grasp this phenomenon well. You’ll have to go there and see for yourself. Or simply, the simulator at the end of this paragraph will help you understand it better.
At poles, the sun almost moves horizontally for many days. It keeps on making a horizontal circle around you. There, it is day for 6 months and night for the next 6 months. [Here is a sun path simulator for Earth]

However, nowhere on earth, things get as interesting as they get in the skies of Mercury.

The sun – as seen from Mercury

On Mercury, the sun appears to briefly reverse its usual east to west motion once every Mercurian year. The effect is visible from any place on Mercury, but there are certain places on its surface, where an observer would be able to see the Sun rise about halfway, reverse and set, and then rise again, all within the same day. It is indeed an unusual performance which isn’t easy for us Earthlings to digest. [See animation in the next paragraph]

Why does it happen?

Let us consider a simpler analogy – some planets (like Mars), as seen from earth, take a similar path. [see the animation for Mars’s path as seen from earth]

The planets, including Earth, all travel around the Sun in a continuous orbit. We can see them make their way across the sky in a straight line usually. However, every now and then a planet appears to turn around. After turning around, it appears to move back the way it came. This is called a retrograde orbit and is caused due to the difference in speeds at which the planets circle the Sun.

So, as we see Mars do a reverse from earth, a similar motion of sun is observed from the surface of Mercury.

[Apparent Retrograde Motion – Wikipedia]

Why is a Metal Plate “Colder” Than a Plastic Plate?

by Anupum Pant

No, it isn’t!

What is Cold?

According to the dictionary, a body at a relatively lower temperature, especially when it is compared to the temperature of a human body is described as a colder one. So, any object below the normal human body temperature – about 37 degrees Celsius – is a cold thing. But wait a minute!

When you touch an object, what does it tell you about the temperature of the object? Can you really judge if it is a cold one or a hot one? Unfortunately, our bodies aren’t thermometers, we are not so smart when it comes to judging the temperature. Consider the following case.

A book and a steel plate kept in the same environment for a long time attain the same temperature eventually (it is called thermal equilibrium). This can be checked by using a thermometer on both the objects. But, when people are asked to touch a metal plate and a book, they find the former to be much cooler. You can try this out yourself by touching different materials around you. You’ll see how some things ‘feel colder’ while the others feel warmer. A YouTube channel Vertasium conducted a social experiment to record this on camera. See the video below:

There is no cold – only heat

So, in the video, ice melts faster, if kept on steel plate than on a plastic plate, even when the steel plate ‘feels colder’. Common sense dictates that the colder thing is supposed to sustain the ice block for a longer time, just like your refrigerator does. So why does the opposite happen?

A better way to understand this ‘contradiction’ (not really a contradiction) can be this:

According to thermodynamics, simply put, everything has heat in it. So, even a cold ice block has some amount of heat stored in it (say, around 273.15 Kelvin or 0 degree Celsius). When one object comes in contact with other object, it loses or gains heat till their temperatures get equal or till they attain ‘thermal equilibrium’. Which object loses heat and which one gains it, is decided by their relative temperatures. In case of ice and steel, ice has a lower temperature than steel (assuming it isn’t already freezing out there). Therefore, here, ice gains heat from steel till they attain the same temperature and ice melts.

Side note: The ice is also in contact with a relatively ‘hotter’ atmosphere. Hence, it gains heat from there also. In this case, we are only concerned about the steel and ice interaction.

Why does it melt faster on steel?

There is a particular property which depends on the kind of material and is called thermal conductivity. This is the parameter which decides which objects lose heat quicker and which ones do it slower.

Here, for instance, steel has a higher thermal conductivity than plastic. Hence, the steel plate gives away heat to the ice block faster than a plastic block does. As a result, ice melts faster on a steel plate than on a plastic one.

Incidentally, this effect can also be used to explain why one plate feels colder than the other, in our hands. Think of it like this, the ice is replaced by our hand. So, a steel plate, due to its better thermal conductivity, draws heat faster from our hand than a plastic plate. This makes us feel that the steel plate is colder than the plastic one.

As checked by a thermometer, both the plates have the same temperature, our bodies are only fooled into believing that the thing we feel is temperature; it isn’t. None of the plates is actually colder than the other (according to the dictionary – see first paragraph). We don’t feel the temperature. What we feel is actually the rate of heat being drawn away from our hand. Faster an object draws heat, the colder it feels.