Advertisements
Advertisements
प्रश्न
A neutron star has a density equal to that of the nuclear matter. Assuming the star to be spherical, find the radius of a neutron star whose mass is 4.0 × 1030 kg (twice the mass of the sun).
Advertisements
उत्तर
Given:
Mass of the neutron star, M = 4.0 × 1030 kg
Density of nucleus , d = `2.4 xx 10^17`
Density of nucleus, d= `M/V`
Here, V is the volume of the nucleus.
`therefore V = M/d = (4 xx 10^30)/(2.4 xx 10^17)`
= `1/0.6 xx 10^13`
= `1/6 xx 10^14`
If R is the radius, then the volume of the neutron star is given by
`V = 4/3piR^3`
`therefore 1/6 xx 10^14 = 4/3 xx pi xx R^3`
⇒ `R^3 = 1/6 xx 3/4 xx 1/pi xx 10^14`
⇒ `R^3 = 1/8 xx 100/pi xx 10^12`
`therefore R = 1/2 xx 10^4 xx 3.17`
= `1.585 xx 10^4 = 15 "km"`
APPEARS IN
संबंधित प्रश्न
In a typical nuclear reaction, e.g.
`"_1^2H+"_1^2H ->"_2^3He + n + 3.27 \text { MeV },`
although number of nucleons is conserved, yet energy is released. How? Explain.
Write the relationship between the size of a nucleus and its mass number (A)?
Using the curve for the binding energy per nucleon as a function of mass number A, state clearly how the release in energy in the processes of nuclear fission and nuclear fusion can be explained.
The mass number of a nucleus is equal to
Which of the following is a wrong description of binding energy of a nucleus?
In one average-life,
For nuclei with A > 100,
(a) the binding energy of the nucleus decreases on an average as A increases
(b) the binding energy per nucleon decreases on an average as A increases
(c) if the nucleus breaks into two roughly equal parts, energy is released
(d) if two nuclei fuse to form a bigger nucleus, energy is released.
Assume that the mass of a nucleus is approximately given by M = Amp where A is the mass number. Estimate the density of matter in kgm−3 inside a nucleus. What is the specific gravity of nuclear matter?
Calculate the mass of an α-particle. Its Its binding energy is 28.2 MeV.
(Use Mass of proton mp = 1.007276 u, Mass of `""_1^1"H"` atom = 1.007825 u, Mass of neutron mn = 1.008665 u, Mass of electron = 0.0005486 u ≈ 511 keV/c2,1 u = 931 MeV/c2.)
(a) Calculate the energy released if 238U emits an α-particle. (b) Calculate the energy to be supplied to 238U it two protons and two neutrons are to be emitted one by one. The atomic masses of 238U, 234Th and 4He are 238.0508 u, 234.04363 u and 4.00260 u respectively.
(Use Mass of proton mp = 1.007276 u, Mass of `""_1^1"H"` atom = 1.007825 u, Mass of neutron mn = 1.008665 u, Mass of electron = 0.0005486 u ≈ 511 keV/c2,1 u = 931 MeV/c2.)
What is the unit of mass when measured on the atomic scale?
The force 'F' acting on a particle of mass 'm' is indicated by the force-time graph shown below. The change in momentum of the particle over the time interval from zero to 8s is:
A nucleus of mass M emits a γ-ray photon of frequency 'v'. The loss of internal energy by the nucleus is ______.
The ratio of wavelengths of the last line of Balmer series and the last line of Lyman series is:
A given coin has a mass of 3.0 g. Calculate the nuclear energy that would be required to separate all the neutrons and protons from each other. Assume that the coin is entirely made of \[_{29}^{63}Cu\] atoms (of mass 62.92960 u).
