Why is there an upper limit to the mass of a white dwarf?
A) The more massive the white dwarf, the higher its temperature and hence the greater its degeneracy pressure. Near 1.4 solar masses, the temperature becomes so high that all matter effectively melts into subatomic particles.
B) White dwarfs come only from stars with masses less than 1.4 solar masses.
C) The upper limit to the masses of white dwarfs was determined through observations of white dwarfs in binary systems, but no one knows why the limit exists.
D) The more massive the white dwarf, the greater the degeneracy pressure and the faster the speeds of its electrons. Near 1.4 solar masses, the speeds of the electrons approach the speed of light, and no more mass can be supported.
D
You might also like to view...
Which type of heavy atomic nuclei are most common, and why?
A) Transuranium elements, for only very heavy elements are made in supernovae. B) Odd numbered elements, because hydrogen is the building block for all heavier elements. C) Even numbered elements, for helium is "giant food" for everything beyond itself. D) Metals, for iron is the last abundant element formed before the type II supernova. E) Noble gases, for they are the most stable elements.
Two identical silver spheres of mass m and radius r are placed a distance R (sphere 1) and 2R (sphere 2) from the Sun, respectively. The ratio of the pressure of solar radiation on sphere 2 to that on sphere 1 is
A. 0.25. B. 0.50. C. 1.0. D. 2.0. E. 4.0.
An old LP record that is originally rotating at 33.3 rad/s has a uniform angular acceleration of 2.15 rad/s2. Through what angle has the record turned when its angular speed reaches 72.0 rad/s?
A) 83.2 rad B) 316 rad C) 697 rad D) 66.8 rad E) 948 rad
A box is dropped onto a conveyor belt moving at 2 m/s. If the coefficient of friction between the box and the belt is 0.3, how long before the box moves without slipping?