A nucleus has mass represented by M (A, Z). If Mp and Mn denote the mass of proton and neutron respectively and BE the binding energy (in MeV), then:
BE = [M(A,Z)-ZMp - (A-Z)Mn]c2
BE = [ZMp + (A-Z)Mn -M(A,Z)]c2
BE = [ZMp + AMn - M (A,Z)]c2
BE = [ZMp + AMn - M (A,Z)]c2
In the following circuit the output Y for all possible input A and B is expressed by the truth table:
A | B | Y |
0 | 0 | 0 |
0 | 1 | 0 |
1 | 0 | 0 |
1 | 1 | 1 |
A | B | Y |
0 | 0 | 1 |
0 | 1 | 1 |
1 | 0 | 1 |
1 | 1 | 0 |
A | B | Y |
0 | 0 | 1 |
0 | 1 | 1 |
1 | 0 | 1 |
1 | 1 | 0 |
A | B | Y |
0 | 0 | 1 |
0 | 1 | 1 |
1 | 0 | 1 |
1 | 1 | 0 |
If the nucleus has a nuclear radius of about 3.6 fm, then
would have its radius approximately as:
6.0 fm
9.6 fm
12.0 fm
12.0 fm
The total energy of an electron in the ground state of a hydrogen atom is -13.6 eV. The kinetic energy of an electron in the first excited state is:
3.4 eV
6.8 eV
13.6 eV
13.6 eV
A.
3.4 eV
The total energy of an electron in the orbit is equal to negative of its kinetic energy.
The energy of hydrogen atom when the electron revolves in nth orbit is
E = -13.6/n2 eV
In the ground state: n =1
E = - -13.6/12 = -13.6 eV
For n = 2, E = -13.6/22 = -3.4 eV
so, the kinetic energy of an electron in the first excited state (i,e, for n = 2 ) is
K = - E = - (-3.4) - 3.4 eV
Monochromatic light of frequency 6.0 x 1014 Hz is produced by a laser. The power emitted is 2 x 10-3 W. The number of photons emitted, on the average, by the source per second is:
5 x 1015
5 x 1016
5 x 1017
5 x 1017
The frequency of a light wave in the material is 2 x 10 Hz and wavelength is 5000 A. the refractive index of material will be:
1.40
1.50
3.00
3.00
In the energy band diagram of a material shown below, the open circles and filled circles denote holes and electrons respectively. The material is a/an,
p-type semiconductor
insulator
metal
metal
A 5 W source emits monochromatic light of wavelength 5000 A. When placed 0.5 m away, it liberates photoelectrons from a photosensitive metallic surface. when the source si moved to a distance of 1.0 m, the number of photoelectrons liberated will be reduced by a factor of:
4
8
16
16
Two radioactive substance A and B have decay constants 5λ and λ respectively. At t = 0 they have the same number of nuclei. The ratio of a number of nuclei of A to those of B will be after a time interval:
1/ 4λ
4λ
2λ
1/2λ
Monochromatic light of frequency 6.0 x 1014 Hz is produced by a laser. The power emitted is 2 x 10-3 W The number of photons emitted, on the average, by the source per second is:
5 x 1015
5 x 106
5 x 1017
5 x 1017