Solution:
As we apply electric field is applied across a semiconductor, the electrons in the conduction band acquire energy and get accelerated. They travel from lower energy level to higher energy level. While the holes in valence band travel from higher energy level to lower energy level, where they will be having more energy.
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In the given circuit, with steady current, the potential drop across the capacitor must be
|
(a) V |
(b) V / 2 |
(c) V / 3 |
(d) 2V / 3 |
A charged particle of mass 5 
is held stationary in space by placing it in an electric field of strength 
directed vertically downwards. The charge on the particle is
|
(a) -20 |
(b) -5 |
(c) 5 |
(d) 20 |
A glass prism (μ = 1.5) is dipped in water (μ = 4/3) as shown in figure. A light ray is incident normally on the surface AB. It reaches the surface BC after totally reflected, if
|
(a) sinθ ≥ 8/9 |
(b) 2/3 < sinθ < 8/9 |
(c) sin θ ≤ 2/3 |
(d) It is not possible |
A coil of wire having finite inductance and resistance has a conducting ring placed coaxially within it. The coil is connected to a battery at time t = 0, so that a time-dependent current 
starts flowing through the coil. If 
is the current induced in the ring. and B(t) is the magnetic field at the axis of the coil due to , then as a function of time (t > 0), the product I2 (t) B(t)
|
(a) Increases with time |
(b) Decreases with time |
|
(c) Does not vary with time |
(d) Passes through a maximum |
A diffraction is obtained by using a beam of red light. What will happen if the red light is replaced by the blue light
|
(a) Bands will narrower and crowd full together |
|
(b) Bands become broader and further apart |
|
(c) No change will take place |
|
(d) Bands disappear |
