Concept explainers
(a)
The speed at which the blazar seems to be drifting away from us when a blazar at
(a)
Answer to Problem 26Q
Solution:
Explanation of Solution
Given data:
Red shift of the blazar is
Formula used:
The expression for Hubble’s Law red shift is written as,
Here,
Explanation:
Write the expression for Hubble’s Law for red shift.
Rearrange this for
Substitute
Conclusion:
Therefore, the speed of the blazar is
(b)
The time period for which the variation in brightness lasted as measured by an astronomer within the blazar’s host galaxy by using the idea of time dilation if a blazar at
(b)
Answer to Problem 26Q
Solution:
Explanation of Solution
Given data:
Red shift of the blazar is
Speed of the blazar is
Formula used:
The expression for time dilation in relativity is written as,
Here,
Explanation:
Write the expression time for dilation in relativity.
Rearrange this for
Substitute
Conclusion:
Therefore, the fluctuation lasted for
(c)
The maximum size
(c)
Answer to Problem 26Q
Solution:
The maximum size of the region of the blazar that emits energy is
Explanation of Solution
Introduction:
Blazars are an example of AGN. All the AGNs are powered by the material which falls into the black hole at the center of a host galaxy. This black hole generates a large amount of energy from the gas and dust.
Explanation:
Blazars emits energy from the surface. This surface is small with respect to the quasar. This is, approximately,
Conclusion:
Therefore, the maximum size of the region of the blazar that emits energy is
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Chapter 24 Solutions
UNIVERSE LL W/SAPLINGPLUS MULTI SEMESTER
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