When hydrogen atom is in its first excited level, its radius is .... its ground state radius
|
(a) Half |
(b) Same |
(c) Twice |
(d) Four times |
When hydrogen atom is in its first excited level, its radius is .... its ground state radius
|
(a) Half |
(b) Same |
(c) Twice |
(d) Four times |
(b) Same
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Assertion : Neutrons penetrate matter more readily as compared to protons.
Reason : Neutrons are slightly more massive than protons.
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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. |
The electron emitted in beta radiation originates from
|
(a) Inner orbits of atoms |
(b) Free electrons existing in nuclei |
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(c) Decay of a neutron in a nucleus |
(d) Photon escaping from the nucleus |
The current in a coil changes from 4 ampere to zero in 0.1 s. If the average e.m.f. induced is 100 volt, what is the self inductance of the coil
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(a) 2.5 H |
(b) 25 H |
(c) 400 H |
(d) 40 H |
An eye specialist prescribes spectacles having a combination of convex lens of focal length 40 cm in contact with a concave lens of focal length 25 cm. The power of this lens combination in diopters is
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(a) + 1.5 |
(b) – 1.5 |
(c) + 6.67 |
(d) – 6.67 |
A molecule with a dipole moment p is placed in an electric field of strength E. Initially the dipole is aligned parallel to the field. If the dipole is to be rotated to be anti-parallel to the field, the work required to be done by an external agency is
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(a) – 2pE |
(b) – pE |
(c) pE |
(d) 2pE |