Question

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

Answer

(b) Same

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Which of the following particles will describe the smallest circle when projected with the same velocity perpendicular to a magnetic field?
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  2. Proton
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Reason     : Neutrons are slightly more massive than protons.

(a) If both assertion and reason are true and the reason is the correct explanation of the assertion.

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(d) Photon escaping from the nucleus

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What is the atomic mass (u) of chlorine?

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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