Suppose you are standing on top of the
Eiffel Tower. You can see the curvature of the Earth and the hundreds of people
walking below you. Then you decided to jump. What would you feel?
You would be in a state called weightlessness, i.e you have no weight.
You would be in a state called weightlessness, i.e you have no weight.
Now suppose you are in a satellite, revolving around
the Earth. What would feel?
At a glance, you would say there is no gravity because you are in space and hence you are floating around. What if, I said, that the action of you falling off the Eiffel Tower and you being in the satellite is the same.
At a glance, you would say there is no gravity because you are in space and hence you are floating around. What if, I said, that the action of you falling off the Eiffel Tower and you being in the satellite is the same.
In the year 1686, Sir Isaac Newton
presented the Universal law of Gravitation in his book Principia Mathematica. It stated that objects attract each other due to
their mass and explained as to why planets orbits around the Sun in an elliptical
manner.
Fast forward to
1915, Albert Einstein thought it was
actually the curvature of space that actually accounted for the motion of
various planetary motion. Think of it
like this. Suppose you have a piece of cloth and along the boundaries of the
cloth, you attach it over a hollow ring. Next, put an object with some mass in
the middle of the setup. Now take a small marble and release it from the
boundary of the ring. You would see that the marble rolls of towards the bigger
object in the middle. Do it again, but this time, push the marble sideways as
you release it. Now you would see that the marble rotates in an elliptical
manner around the heavier object as it slowly and slowly rolls down.
This is what
Einstein imagined gravity as. All objects with mass actually rest on a piece of
fabric called space-time. Anything with mass cause a depression in the
space-time fabric. So when an object falls, it is actually following the
depression of the fabric caused by the mass of the heavier object. So matter
and energy tells how the space-time fabric to curve and in return, the
space-time fabric tells how matter and energy should move. Einstein’s
visualized a new theory of gravity which successfully explained the ripples in
gravity caused by black holes or the bending of light near stars.
As in the case of
falling and floating in space, in both cases, gravity is acting upon you. You
are falling towards the Earth but the only difference is that while in space
you are actually falling and moving sideways, at a rate which perfectly aligns
with the curvature of the Earth.
Regards,
Sanjay Dutta
CSE-C, 2nd year
CSE-C, 2nd year
Good Sanjay
ReplyDeleteThank you Sir
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