Mpdenotes the mass of a proton and Mn that of a
neutron. A given nucleus, of binding energy B, contains Z protons and N neutrons. The massM(N,Z) of the nucleus is given by ( c is the velocity of light )
The work function for metals A, B and C are respectively 1.92 eV, 2.0 eV and 5 eV. According to Einstein’s equation, the metals which will emit photoelectrons for a radiation wavelength 4100 Å is/are.
None
A only
A and B only
All three metals
Fission of nuclei is possible because the biding energy per nucleon in them
Increases with mass number at low mass numbers
Decreases with mss number at low mass
Increases with mass number at high mass numbers
Decreases with mass number at high mass numbers.
The binding energy of deuteron is 2.2 MeV and that of is 28. If two deuterons are fused to form one , then the energy released is
23.6 MeV
19.2 MeV
30.2 MeV
25.8 MeV
An oscillator is nothing but an amplifier with
Positive feedback
Negative feedback
Large gain
No feedback
When a P-N junction diode is reverse biased the flow of current across the junction is mainly due to
Diffusion of charge
Drift charges
Depends on the nature of material
Both drift and diffusion of charges
The current gain for a transistor working as common-base amplifier is 0.896. If the emitter current is 7.2 mA, then the base current is
0.29 mA
0.35 mA
0.39 mA
0.43 mA
When a n-p-n transistor is used as an amplifier then
The electrons flow from emitter to collector
The holes low from emitter to collector
The electrons flow from collector to emitter
The electrons flow from battery to emitter
In a p-n junction photo cell, the value of the photo –electromotive force produced by monochromatic light is proportional to
The voltage applied at the p-n junction
The barrier voltage of the p-n junction
The intensity of the light falling on the cell
The frequency of the light failing on the cell
Application of a forward bias to a p-n junction
Widens the depletion zone.
Increases the potential difference across the depletion zone.
Increases the number of donors on the n side.
Increases the electric filed in his depletion zone.