IF THE UNIVERSE IS SHRUNK TO THE SIZE OF A EARTH ,THEN WHAT IS THE SIZE OF THE EARTH?
LIGHT EMMITED BY A GUASER TAKES 2 BILLION OF YEARS TO REACH EARTH.FIND THE DISTANCE OF GUASER FROM EARTH?

Asked by Amarnath Gupta | 26th Apr, 2014, 10:23: PM

Expert Answer:

1) The current size of the observable universe is around 1027 m.
The size of our Earth is 106 m.
 
Hence, if the universe is shrunk to the size of Earth, then mathematically this is 1/1021 of its original size. Hence, if we go mathematically then the size of Earth should shrink to a size of
 
10 to the power of 6 over 10 to the power of 21 equals 10 to the power of minus 15 end exponent space straight m
 
This is the size of a nucleus.
 
Now, If we go by Physics if the universe actually shrunk to this size, then its gravity will be so immense that no matter can exist inside it as a solid entity. Hence, Earth wont exist as a planet and it would have been ripped apart into atoms and smaller particles.
 
2) Light from Quasar reaches Earth after 2 billion years. Hence, its distance is
 
straight d equals 2 space billion space light space years equals 2 cross times 10 to the power of 9 space light space years Now comma space 1 space ly equals 9.46 cross times 10 to the power of 15 space straight m Hence comma space we space have straight d equals 2 cross times 10 to the power of 9 cross times 9.46 cross times 10 to the power of 15 equals 1.89 cross times 10 to the power of 25 space straight m

Answered by  | 28th Apr, 2014, 12:02: PM

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