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 Question: What is the reason behind corona heating problem? By: mani     Date: 2012-08-26 Answer: It is currently believed tat the coronal heating is possibly an outcome of two processes: 1. The reconnection of magnetic flux tubes 2. The transport of energy through waves that propagate out along the magnetic flux tube. By: Prof. S. Bharadwaj     Date: 2012-09-11

 Question: Could you please throw some more light on siderial day ? By: Satish     Date: 2012-10-08 Answer: Sidereal Day refers to the time period of earth's rotation with respect to distant stars which appear approximately fixed on the sky. This is different from the Solar Day which is the rotation period with reference to the Sun. It may also be noted that the Sidereal Day is actually defined with reference to the position of the vernal equinox instead of distant stars - this causes an additional small difference. By: Prof. S. Bharadwaj     Date: 2012-11-02

 Question: After I watched your lectures, I'm interesting to know the following answer from you professor: Are we alone in this universe? Thanks Prof. By: Ali     Date: 2012-10-27 Answer: Till date there is no evidence for intelligent life outside Earth. By: Prof. S. Bharadwaj     Date: 2012-11-02

 Question: why does every particle attract every other particle?? is there a mathematical proof for newtons law of gravity with respect to quantum physics? By: rachana.s.yajur     Date: 2012-12-06 Answer: Newton's Law of Gravity cannot be "proven". It is introduced to explain the observed behaviour of particles. The Law can be obtained as a limit from the General Theory of Relativity. By: Prof. S. Bharadwaj     Date: 2012-12-11

 Question: what happens to the force of gravity if the distance between the two objects is zero? By: rachana.s.yajur     Date: 2012-12-08 Answer: It becomes infinitely large. By: Prof. S. Bharadwaj     Date: 2012-12-11

 Question: what is anti gravity?where does it exist in the universe? By: rachana.s.yajur     Date: 2012-12-26 Answer: To the best of my knowledge there is no such thing as anti-gravity. By: Prof. S. Bharadwaj     Date: 2012-12-28

 Question: Sir, regarding the qn about antigravity, can we say that dark energy is like antigravity,albiet on a much grander scale?Also,can we say that when dist b/w 2 bodies is very close, quantum effects comes in & changes the result to smthg non-infinite? I thought gen rel. can solve the problem By: Arun.V     Date: 2013-01-02 Answer: According to the currently accepted paradigm, the answer to your question is NO. However, you are free to try and develop an alternate perspective and see if it works. By: Prof. S. Bharadwaj     Date: 2013-01-21

 Question: Sir, to the qn abt proof of newtons law,can we start from eqn of continuty & gauss law for gravtn to prove the 1/r^2 nature,just like in electrostatics.In that case value of G will come from experiment;we can only prove the dependency on r.Also,T.Padmanabhan xplain y grav is attr in his gravitn boo By: Arun.V     Date: 2013-01-02 Answer: You cann start from Poisson Eq. and derive Newton's law of gravity and vice-versa, they are equivalent. By: Prof. S. Bharadwaj     Date: 2013-01-21

 Question: When Earth's come closer to the Sun,is their any change in dimension(expansion) of Earth due to Sun's heat and gravitation ? By: Alok Shaw     Date: 2013-01-27 Answer: There will be changes on Earth if it were to move closer to the Sun. By: Prof. S. Bharadwaj     Date: 2013-02-01

 Question: sir,why does the moon not fall into the sun and revolve around the earth,even though the gravitational force on moon by sun is greater than by earth? By: ANUPAM     Date: 2013-02-18 Answer: Earth's gravitational pull exceeds that of the Sun. By: Prof. S. Bharadwaj     Date: 2013-02-24
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