- A$\text{V}$
- B$\sqrt{\text{V}}$
- C$\text{T}$
- D$\sqrt{\text{T}}$
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If n, e, τ and m respectively represent the density, charge relaxation time and mass of the electron, then the resistance of a wire of length l and area of cross-section A will be
|
(a) |
(b) |
(c) |
(d) |
Light of wavelength 4000 Å falls on a photosensitive metal and a negative 2V potential stops the emitted electrons. The work function of the material (in eV) is approximately (h = 6.6 ![]()
|
(a) 1.1 |
(b) 2.0 |
(c) 2.2 |
(d) 3.1 |
n electron is moving on a circular path of radius r with speed v in a transverse magnetic field B. e/m for it will be
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(a) |
(b) |
(c) Bvr |
(d) |
The magnetic field at a point x on the axis of a small bar magnet is equal to the field at a point y on the equator of the same magnet. The ratio of the distances of x and y from the centre of the magnet is
|
(a) |
(b) |
(c) |
(d) |
Two infinite plane parallel sheets separated by a distance d have equal and opposite uniform charge densities σ. Electric field at a point between the sheets is
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(a) Zero |
(b) |
|
(c) |
(d) Depends upon the location of the point |