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My question is that if the sun goes off just now,when will we feel it?Is the time
Immedietly
after 8 mins 32 seconds
before this interval but not immediately
after this interval?
I have got different answers from different sources.But which is the truth?

I choose the second option.because, nothing goes faster than light

Well, Sanzeed, Einstein's Theory of Relativity states that Gravitational Force manifests itself in the curvature of Space ad Time, and travels in the form of Gravitational Waves which travel at the speed of light. So, it would take us exactly 8 minutes and 32 seconds (i.e, the time required for light to travel to Earth) to realize that the sun is not there if it disappeared suddenly. ( I got this information off a Discovery Channel Documentary )
By the way, Congratulations.....Sanzeed, for securing the 2nd place in the Junior level of Vasa Protiog.
May your life be full of such successes.

that's right. everything we know about is limited to the speed of light, even gravitation.

But @sowmitra vaia, please read "Podarthobiddar Mojar Kotha" by Yacov Perelman.He differs with your opinion.

SANZEED wrote:But @sowmitra vaia, please read "Podarthobiddar Mojar Kotha" by Yacov Perelman.He differs with your opinion.

As far as I know, that book was written before Gravitational waves were discovered.

Actuaally gravitational waves were discovered by Einstein. It is one of the first things of general relativity. If Perelman said that we can know that the sun is gone faster than light, then he is wrong. No information (including gravitation) can travel faster than light, not even quantum information.

The book "Physics for entertainment" (which was translated to "পদার্থবিদ্যার মজার কথা") was written in 1913 [src], while Einstein first predicted gravitational waves in 1916 [src]. So, what Perelman wrote in his book is correct by what was known at that time , but of course that is wrong as we know about gravitational waves now.

:O

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I think the editions should be corrected, now