Threshold wavelength for photoelectric effect on sodium is 5000 Å. Its work function is
|
(a) 15 J |
(b) 16 |
(c) 4 |
(d) 4 |
Threshold wavelength for photoelectric effect on sodium is 5000 Å. Its work function is
|
(a) 15 J |
(b) 16 |
(c) 4 |
(d) 4 |
(c) 4
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Metallic solids are always opaque because
|
(a) Solids effect the incident light |
|
(b) Incident light is readily absorbed by the free electron in a metal |
|
(c) Incident light is scattered by solid molecules |
|
(d) Energy band traps the incident light |
The mass number of a nucleus is equal to the number of
|
(a) Electrons it contains |
(b) Protons it contains |
|
(c) Neutrons it contains |
(d) Nucleons it contains |
A long horizontal metallic rod with length along the east-west direction is falling under gravity. The potential difference between its two ends will
|
(a) Be zero |
(b) Be constant |
(c) Increase with time |
(d) Decrease with time |
A convex lens is used to form real image of an object on a screen. It is observed that even when the positions of the object and that screen are fixed there are two positions of the lens to form real images. If the heights of the images are 4 cm and 9 cm respectively, the height of the object is
|
(a) 2.25 cm |
(b) 6.00 cm |
(c) 6.50 cm |
(d) 36.00 cm |
Two condensers of capacity 0.3 μF and 0.6 μF respectively are connected in series. The combination is connected across a potential of 6 volts . The ratio of energies stored by the condensers will be
|
(a) |
(b) 2 |
(c) |
(d) 4 |
If the wavelength of light is 4000 Å, then the number of waves in 1 mm length will be
|
(a) 25 |
(b) 0.25 |
(c) 0.25 |
(d) 25 |