The de-Broglie wavelength λ associated with an electron having kinetic energy E is given by the expression
|
(a) |
(b) |
(c) 2mhE |
(d) |
The de-Broglie wavelength λ associated with an electron having kinetic energy E is given by the expression
|
(a) |
(b) |
(c) 2mhE |
(d) |
(a)
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Symbolic representation of photodiode is
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(a) |
(b) |
(c) |
(d) |
The current carrying wire and the rod AB are in the same plane. The rod moves parallel to the wire with a velocity v. Which one of the following statements is true about induced emf in the rod

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(a) End A will be at lower potential with respect to B |
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(b) A and B will be at the same potential |
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(c) There will be no induced e.m.f. in the rod |
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(d) Potential at A will be higher than that at B |
If the energy of a hydrogen atom in nth orbit is
, then energy in the nth orbit of a singley ionized helium atom will be
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(a) 4 |
(b) |
(c) 2 |
(d) |
The electric intensity E, current density j and specific resistance k are related to each other by the relation
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(a) E = j/k |
(b) E = jk |
(c) E = k/j |
(d) k = jE |
A nucleus with mass number 220 initially at rest emits an a-particle. If the Q value of the reaction is 5.5 MeV, calculate the kinetic energy of the a-particle
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(a) 4.4 MeV |
(b) 5.4 MeV |
(c) 5.6 MeV |
(d) 6.5 MeV |
Assertion : X-rays are used for studying the structure of crystals.
Reason : The distance between the atoms of crystals is of the order of wavelength of X-rays.
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(a) If both assertion and reason are true and the reason is the correct explanation of the assertion. |
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(b) If both assertion and reason are true but reason is not the correct explanation of the assertion. |
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(c) If assertion is true but reason is false. |
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(d) If the assertion and reason both are false. |