12th Class Physics MCQS
When platinum is heated is become dull red at:
1100°C
900°C
500°C
800°C
If the energy of photon is 10 eV and work function is 5 eV, then the a value of stopping potential will be
2 V
5 V
50 V
15 V
A perfect absorber must also be perfect
Radiator
None of these
Cavity
Sources of radiation
We can never accurately describes all aspects of sbatomic particles simulatanously. It is correct according to:
Einstin Theory
Photo electric effect
Uncertainity Priciple
De-broglie Theory
The Compton effect is associated with
ß-rays
Positive rays
X-rays
y-rays
The position has charge which is in magnitude equal to the charge on
Proton
? particle
All
Electron
Pair production occurs only when energy of photon is at least equal in:
1.02 MeV
1.02keV
1.02 GeV
1.02 eV
The converses of annihilation of matter is:
Pair production
Compton effect
Relativistic effect
Photoelectric effect
Pair production cannto take place in vacuum because :
Momentum is not conserved
Charge is not conserved
Mass in not conserved
Energy is not conserved
The unit of work function is
Ampere
Hz
Volt cell
Electron volt
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