Concept explainers
(a)
The density of matter in a neutron and compare it with the average density of a neutron star. It is given that neutron has a mass of
(a)
Answer to Problem 13Q
Solution:
The density of neutron is
Explanation of Solution
Given data:
The mass of a neutron is
Formula used:
Write the expression for density:
Here,
Write the expression for volume of a sphere:
Here,
Explanation:
Let’s assume that neutron is a sphere of radius
According to question, mass of neutron is
Calculate the volume of a sphere.
Refer to the expression for volume of sphere,
Substitute
Calculate density of neutron.
Refer to the expression of expression for density of a neutron star,
Substitute
Now, compare the density of matter in a neutron with average density of a neutron star.
As average density of neutron in neutron star is
Conclusion:
Hence, neutron has density of
(b)
Neutrons within a neutron star are overlapping if density of neutron star is more than that of neutron, or are underlapping otherwise. Also, explain whether density at the center of a neutron star is higher than the average density of neutron star. It is given that neutron has mass of
(b)
Answer to Problem 13Q
Solution:
As the density of neutron is less than the average density of a neutron star, therefore, neutrons in the neutron star are in overlapping state and density is uniform throughout the neutron star.
Explanation of Solution
Given data:
The mass of neutron is
Introduction:
A neutron star is composed of an incredibly dense sphere of neutrons formed by a supernova explosion. Its average density is about
Explanation:
Refer to part (a) of the question, the average density of neutron in a neutron star is
From the above observation, neutrons in the neutron star are overlapping as density of a neutron is less than the average density of a neutron star.
Also, in a neutron star, density is uniform throughout. In other words, density at the center is same as density at the surface of neutron star.
Conclusion:
Hence, neutrons in the neutron star are in overlapping state.
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Chapter 21 Solutions
Universe
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