Semiconductor Electronic: Material, Devices And Simple Circuits — Physics STD 12 Science — Question

Resistivity of a wire depends on:

The resistance of a heater coil is 110 ohm. A resistance R is connected in parallel with it and the combination is joined in series with a resistance of 11 ohm to a 220 volt main line. The heater operates with a power of 110 watt. The value of R in ohm is

(a) 12.22	(b) 24.42
(c) Negative	(d) That the given values are not correct

The Sun's mean density is:

Each plate of a parallel plate capacitor has a charge q on it. The capacitor is now connected to a batter. Now:

In the following circuit a 10 m long potentiometer wire with resistance 1.2 ohm/m, a resistance R₁ and an accumulator of emf 2 V are connected in series. When the emf of thermocouple is 2.4 mV then the deflection in galvanometer is zero. The current supplied by the accumulator will be

(a) 4 × 10–4 A

(b) 8 × 10–4 A

(c) 4 × 10–3 A

(d) 8 × 10–3 A

Current through wire XY of circuit shown is

(a) 1 A

(b) 4 A

(c) 2 A

(d) 3 A

The amount of energy that a unitary point electric charge would have, if located at any point in space, is defined its:

The S.I. unit of electric flux is

(a) Weber	(b) Newton per coulomb
(c) Volt  × metre	(d) Joule per coulomb

In a negative logic the following wave form corresponds to the

(a) 0000000000

(b) 0101101000

(c) 1111111111

(d) 1010010111