Zenor breakdown in a semiconductor diode occurs when
Options
(a) Forward current exceeds certain value (b) Reverse bias exceeds certain value (c) Forward bias exceeds certain value (d) Potential barrier is reduced to zero
Masses of 3 wires of same metal are in the ratio 1:2:3 and their lengths are in the ratio 3:2:1. The electric resistances are in the ratio
Options
(a) (1:4:9) (b) (9:4:1) (c) (1:2:3) […]
The cadmium rods are used in nuclear reactor to
Options
(a) Speed up neutrons (b) Slow down neutrons (c) Emit neutrons (d) Absorb some neutrons
Correct Answer:
Absorb some neutrons
Explanation:
No explanation […]
The coefficient of performance of a Carnot refrigerator working between 30⁰C and 0⁰C is
Options
(a) 10 (b) 1 (c) 9 (d) zero
Correct Answer:
9
Explanation:
Coefficient of performance = K .·. […]
A cricketer can throw a ball to a maximum horizontal distance of 100 m. With the same effort, he throws the ball vertically upwards. The maximum height attained by the ball is
Options
A body of weight W newton is at the surface of the earth. Its weight at a height equal to half the radius of the earth will be
Options
(a) W/2 (b) 2W/3 […]
For an ideal gas of diatomic molecules
Options
(a) Cp = 5R / 2 (b) Cv = 3R / 2 (c) Cp – Cv = 2R (d) Cp = 7R / 2
Correct […]
Under constant pressure, graph between P and 1/V is a
Options
(a) parabola (b) hyperbola (c) straight line (d) circle
Correct Answer:
straight line
Explanation:
No explanation available. Be the first to write […]
The innermost orbit of hydrogen atom has a diameter 1.06Å. The diameter of tenth orbit is
Options
(a) 5.3 Å (b) 10.6 Å (c) 53 Å (d) 106 Å
Correct Answer:
106 Å
A charge of 40 µC is given to a capacitor having capacitance C=10 µF. The stored energy in erg is
Options
(a) 80 x 10⁻⁶ (b) 800 (c) 80 (d) 8000
Correct Answer: […]
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