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Can we travel faster than the speed of light?
Our universe is very big.
It consists of numerous galaxies, stars, planets, etc.
However, until now, we are able to examine
only a few of them.

So, in order to cross vast distances and explore distant places, we need to travel very fast.
Now, it is observed that nothing can travel
faster than the speed of light.

Which is about 186,282 miles per second.
This means light from earth will take only
1.3 seconds to reach the moon.

Let's compare this to the Apollo 11 spacecraft that took 75 hours.
56 minutes to just enter the orbit of the moon.
So, imagine if we could travel faster than
light, then space travel would be so easy.

We could time travel and even see our future.
However, traveling faster than light is impossible.
Do you know why?
According to Einstein's theory of relativity,
to move an object, we require energy.

Now, to make this moving object move faster or speed up, we require even more energy.
So, what do you think?
How much energy will be required to make an object move at the speed of light?
If we again refer to the Einstein's theory
of relativity.

We can conclude that it will require an infinite amount of energy to make an object move at the speed of light.
But, looking at the current situation, neither
do we have the necessary resources.

Nor do we have the technology to produce an infinite amount of energy.
Hence, we cannot travel at the speed of light or faster.
Moreover, just like a sonic boom is produced by an object traveling faster than sound.
Similarly, a huge amount of radiation will
be produced by an object traveling faster than light.

This radiation can lead to serious consequences.
Hence, it is impossible to travel faster than
the speed of light.

Why is fluoride added to water?
To make water taste like soft drink.
According to a prevailing study.
When fluoride is added to public water supplies at an average concentration of about 1 part per million or slightly below.
It prevents tooth decay.
But how?
Enamel is the hard outer covering of our tooth.
It is primarily made up of hydroxyapatite.
Hydroxylapatite is a compound of calcium,
phosphorus and hydroxide.

Now, when bacteria in our mouth feed on food particles, they produce acid.
This acid dissolves the hydroxyapatite, leaving behind a residue of calcium and phosphate ions.
This results in a tooth decay.
Now, when we drink water containing fluoride.
The fluoride binds with calcium and phosphate ions, forming fluorapatite.
As fluorapatite is less susceptible to acid
attacks, it helps to stop the tooth decay process.

What is sleep paralysis?
No idea.
Sleep paralysis is a condition in which we are conscious but temporarily unable to move or speak.
It can usually occur when we suddenly wake up during REM sleep.
What is REM sleep?
Basically, there are four stages of sleep.
One of them is Rapid eye movement sleep, i.e., REM sleep.
In this stage, we dream.
Researchers suggest that when we enter REM sleep.
Two chemicals, glycine and GABA ''switch off'' the activity of cells in the brain that allow our muscles to move.
Oh no.
This is so bad.
It is actually beneficial because paralyzed
muscles prevent us from enacting our dreams in reality and getting hurt.

However, sometimes we suddenly wake up during REM sleep.
But if glycine and GABA are still active.
We are temporarily unable to move, even though we are conscious.
This is called sleep paralysis.
Can animals predict natural disasters?
I don't know dude.
I'll explain.
It is believed that animals can hear certain
sounds or detect certain changes prior to disasters.

Thus, perceive the upcoming danger.
But how dude?
The initial activities which lead to earthquakes, tsunamis, etc.
Create infrasounds which arrive faster than the main shockwave.
These sounds are inaudible to humans.
But animals like flamingos, elephants, rhinoceroses, etc. can hear them.
Thus, they perceive the coming danger and
probably escape.

It is also said that the earth's magnetic
field slightly deflects before an earthquake.

It is suspected that dogs detect this deflection and thus, predict the arriving disaster.
Some researchers also think that birds can
foresee the approaching storm or tornado.

Because they detect changes in atmospheric pressure, wind speeds, temperature, etc.
Hence, they fly away to a safer place.
Topic: Specific heat of water.
Why is water used in hot water bags?
Looks like your leg is hurting.
Use this hot water bag.
It will give you some warmth and provide you relief.
The bandage is not going to help See.
I told you.
At least now will you use this hot water bag?
You are feeling better, right?
Do you know how a hot water bag gave you warmth for such a long time?
This is due to a concept called specific heat.
Specific heat of a substance is the amount
of heat energy absorbed or lost by that substance to change its temperature.

Now, the hot water bag consists of hot water.
As compared to other liquids like milk and
acetone, the specific heat of water is much higher.

This means that as compared to others.
Water needs to absorb a large amount of heat to become hotter.
Now, did you know that water will take a long time to cool down as comapred to milk and acetone?
Thus, water will take a longer time to become cool.
Hence, it proves to be very useful in hot water bags because the warmth can be utilized for a longer time.
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Can we Travel Faster than Light? | #aumsum

38 Folder Collection
AumSum published on April 13, 2019
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