Question 1 :
If the amplification factor of a triode $(\mu)$ is $22$ and its plate resistance is $6600\ ohm$ , then the mutual conductance of this value in mho is

Question 3 :
If the radius of a copper wire carrying a current is doubled, the drift velocity of the electrons will

Question 4 :
Assertion: Bending a wire does not effect electrical resistance. Reason: Resistance of wire is proportional to resistivity of material.

Question 6 :
Four wires of the same diameter are connected, in turn, between two points maintained at a constant potential difference. Their resistivity's and lengths are; $\rho$ and L (wire $1$), $1.2$ $\rho$ and $1.2$L (wire $2$), $0.9\rho$ and $0.9$L (wire $3$) and $\rho$ and $1.5$L (wire $4$). Rank the wires according to the rates at which energy is dissipated as heat, greatest first.

Question 9 :
A constant voltage is applied between the two ends of a uniform metallic wire. Some heat is developed in it. The heat developed is double if:

Question 10 :
Assertion: The equation $V= Ri$. does not apply to those conducting devices which do not obey Ohm's law. Reason: $V= Ri$ is a statement of Ohm's law.

Question 12 :
The force between two electrons when placedair is equal to 0.5 times the weight of an electrons find the distance between two electrons (mass<span>electron $= 9.1 \times 10 ^ { - 31 } \mathrm { kg } )$</span>

Question 13 :
Assertion: For good conductors, the $I-V$ graph is a perfect straight line inclined to current axis. Reason: By Ohm's law, voltage across the ends of a conductor is directly proportional to the resistance of the conductor.

Question 14 :
Which one of the following statements does not represents Ohm's law?

Question 16 :
When a steady current of $1 A$ flows through a&#160;copper wire, the number of electrons crossing any cross-section area of the wire in one second&#160;<span>is ______.</span>

Question 17 :
Two rods of same material and length have their electric resistance in ratio $1:2$. When both rods are dipped in water, the correct statement will be

Question 18 :
Assertion: Ohm's law is not valid if current depends on voltage non-linearly. Reason: Ohm's law is a fundamental law of nature.

Question 20 :
When connected to the 220V mains supply, the current in a toaster, a kettle, a lamp and a fan is 5.2A, 9.4A, 0.5A and 2.6A respectively. Which appliance has the greatest electrical resistance?

Question 21 :
Two parallel straight conductors carrying currents 5A each repel other with a force of $25 \times 10^{-5} Nm^{-1}$. The distance between the conductors is

Question 22 :
If instantaneous current in a circuit is given by$l=(3+4sin\omega t)A$ os then the maximum value of current in the circuit is

Question 23 :
A current of $I$ ampere flows through a resistance $R$&#160;when connected across a cell of emf&#160;$E$&#160;and internal resistance&#160;$1 \Omega$. When $R$ is increased by $50\%$,&#160;the current&#160;through the circuit is $0.8 A$. The value of $R$ is :