WHEN THE CAR'S AIR-BAG WILL DEFLATE ?

We assume that we know everything about the elementary concept "acceleration". But there is more to know.

Definition: Whenever a body undergoes change in speed or change in direction, it said to be "accelerating".

We know, if any body falls freely, its speed will increase by 9.8m/s^2 for every second due to earth's gravity and it is denoted by the symbol 'g'. Also, we can say, if a body experiences 9.8 m/sˆ2 acceleration, it is acted upon by 'one g' force.

If you plop down on a chair, you will experience up to 10 g force for a brief time.
Even your sneeze will put you in a '2.5g' force. In a thrill ride of roller coaster, we experience 'high g' for a very brief time. There are 'human centrifuge' which creates 'high g' by spinning fast. pilots and astronauts are trained to experience 'high g' in these centrifuges.

When a car crashes, it suddenly decelerates (negative acceleration). The airbag in front of all the seats will be inflated only if the acceleration exceeds '60g'. Prince Diana's car crash produced '70-100g' force. A word of caution. If you experience a force of 4g-6g for a long time, you will be "blacked out". Our body has many organs with different densities and masses. Hence each will get its own g - force.

Feather or boulder; earth always gives 'one g' force to everything. It is because gravitational force proportionally increases with the mass [g = force/mass ].

In pole-vault jump, the person falls on the cushion, to reduce g- force. In a car, the engine is mounted on front and luggage is kept on the back to reduce the effect of g-force in an impact.
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THE EARTH, A SUPER ORGANISM

JOIN MY COURSE: "Become a programmer in a day with python" A man called 'love lock' (what a name) proposed a theory called Gaia theory, named after Greek Goddess. It says, "Earth is a self-regulating organism like a human being. The organic life in it interacts with in-organic matter and maintains atmosphere, temperature and environment". Hence the earth is still suitable for the life to thrive. Imagine, in a particular place, there are lot of flowers. Some flowers are white and some are darkly coloured. We know, white reflects light and heat while dark absorbs the same. White flowers can thrive in hot climate. But dark flowers requires cold climate. The absorption and reflection balances and the environment reaches average, warm temperature at which both the flowers can co-exist. This is the essence of "Gaia" theory. On our earth, ...

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DISORDER IS THE "ORDER OF THE DAY"

Imagine a balloon full of air. The air molecules are moving randomly inside the balloon. Let us pierce the balloon with a pin. The air rushes out. Why should not the air molecules stay inside the balloon safely and ignore the little hole? That is not the way the world works. The molecules always "want to occupy as many states as possible". Hence the air goes out in the open to occupy more volume. The things always goes into disorder (entropy) and the disorder increases with time. The above statement is what we call "second law of thermodynamics". Consider a cup of coffee on the table. Suppose the heat from entire room flows to your cup of coffee, the coffee will boil and the rest of the room will freeze. Freezing means bringing things to order and arrangement. It violates the second law. Hence it will never happen. Hence heat must flow from high ...

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