When a fissionable material like uranium absorbs a neutron, a compound nucleus is formed. This compound nucleus breaks into fragments in
Seconds.
10-8
10-6
10-2
10-15
Which is heaviest compared to that of electron?
(-meson
(-meson
Neutrino
Positron
A near UV photon of 300 nm is absorbed by a gas and then re-emitted as two photons. One photon is red with wavelength 760 nm. Hence, wavelength of the second photon is:
460 nm
1060 nm
496 nm
300 nm
Select correct statement:
Visible light consists of electromagnetic waves of oscillating electric and magnetic fields
In vacuum, all types of electromagnetic radiations travels at the same speed
Both are correct statements
None is correct statement
Electron falls from seventh energy level and lower energy level to give bands in Paschen series. Total number of bands obtained are:
4
3
2
1
The energy of electron in the ground state of hydrogen atom is -13.6 eV and first excited state (n=2) is -3.4 eV. Therefore the resonance potential for hydrogen is
10.2 V
17.0 V
5.1 V
8.5 V
The electron in the hydrogen atom passes from n=4 energy-level to the n=1 level. What is the maximum number of photons that can be emitted?
One
Two
Three
Four
Which of the following quantum number are strictly required for specifying completely the state of any particular electron in the presence of a strong magnetic field which breaks the coupling between orbital and spin quantum number in the electron?
Spin quantum number
Magnetic spin quantum number
Magnetic total angular momentum quantum number
Magnetic orbital quantum number
An X-ray machine is operated at 80 kilo volts; the short wavelength limit of continuous X-ray is equal to
0.155 Ao
1.155 Ao
3.25 Ao
0.275 Ao
The increasing order (lowest first) for the values of e/m (change/mass) for electron (e), proton (p), neutron (n) and alpha particle (() is:
e, p, n, (
n, p, e, (
n, p, (, e
n, (, p, e