- ACm
- BCm2
- CC/m2
- DNone
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The energy of hydrogen atom in its ground state is – 13.6 eV. The energy of the level corresponding to the quantum number n is equal 5 is
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(a) – 5.40 eV |
(b) – 2.72 eV |
(c) – 0.85 eV |
(d) – 0.54 eV |
In Young’s double slit experiment, the distance between the two slits is made half, then the fringe width will become
|
(a) Half |
(b) Double |
(c) One fourth |
(d) Unchanged |
If the central portion of a convex lens is wrapped in black paper as shown in the figure

|
(a) No image will be formed by the remaining portion of the lens |
|
(b) The full image will be formed but it will be less bright |
|
(c) The central portion of the image will be missing |
|
(d) There will be two images each produced by one of the exposed portions of the lens |

A convex mirror has a focal length f. A real object is placed at a distance f in front of it from the pole produces an image at
|
(a) Infinity |
(b) f |
(c) f/2 |
(d) 2f |
A current of two amperes is flowing through a cell of e.m.f. 5 volts and internal resistance 0.5 ohm from negative to positive electrode. If the potential of negative electrode is 10V, the potential of positive electrode will be
|
(a) 5 V |
(b) 14 V |
(c) 15 V |
(d) 16 V |
