A diode valve is connected to a battery and a load resistance. The filament is heated so that a constant current is obtained in the circuit. As the cathode continuously emits electrons, does it get more and more positively charged?

A P-N junction diode connected to a battery of e.m.f. 4.5 V and an external resistance of 1000 Omega . What is the value of current in the circuit, if potential barrier in the diode = 0.5 V

In a Coolidge tube, electrons strike the target and stop inside it. Does the target get more and more negatively charged as time passes?

An inductor of 3H is connected to a battery of emf 6V through a resistance of 100 Omega . Calculate the time constant. What will be the maximum value of current in the circuit ?

Two junction diodes, one of germanium (Ge) and other of silicon (Si) are connected as shown in fig to a battery of 12 V and a load resistance 10 kOmega . The germanium diode conducts at 0.3 V and silicon diode at 0.7 V . When current flows in the circuit, the potential of terminal Y will be .

An ammeter with resistance R_A is connected in series with a resistor R, a battery of emf c and internal resistance r . The current measured by the ammeter is I_A . Find the current through the circuit if the ammeter is removed so that the battery and the resistor form a complete circuit. Express your answer in terms of I_A, r, R_A and R . Show that more "ideal" the ammeter, the smaller the difference between this current and the current I_A . ltbr. (b) If R = 3.80 Omega, epsilon = 7.50 V and r = 0.45 Omega , find the maximum value of the ammeter resistance R_A so that I_A is within 99% of the current in the circuit when the ammeter is absent. (c) Explain why your answer in part (b) represents a maximum value.

A 10 V battery connected to 5omega resistance coil having inductance 10 H through a switch drives a constant current in the circuit. The switch is suddenly opened and the time taken to open it is 2ms. The average emf induced across the coil is

The separation between the plates of a parallel plate capacitor , connected to a battery (zero resistance) of constant EMF is increased with constant (very slow) speed by external forces . During the process, w is the work done dy external forces. DeltaU is the change in potential energy of the capacitor , w_b is work done by the battery and H is the heat loss in the circuit . Then

A battery has an open circuit potential difference 10 V between the terminals. When loads 9Omega and 4 Omega are connected one by one across the battery , the power in the load resistance is the same. The amount of heat approximately generated in one second in the load when a load of 5Omega Is connected across the battery will be

A car bulb connected to a 12 volt battery draws 2 A current when glowing . What is the resistance of the filament of the bulb ? Will the resistance be more, same or less when the bulb is not glowing ?

An ammeter is connected to measure the current intensity in a circuit with a resistance R. What relative error will be made if connection of the ammeter does not change the current intensity in the circuit? The voltage across the ends of the circuit is kept constant.