Current Electricity Physics - Current Electricity

Which of the following has a negative temperature coefficient of

Ohm’s Law is not obeyed by

A steady current is set up in a metallic wire of a non-uniform cross-section. How is the rate of flow K of electrons related to the area of cross-section A?

n resistances, each of r Ω, when connected in parallel give an equivalent resistance of R Ω. If these resistances were connected in series, the combination would have resistance in horns equal to

Charging is a process of reproducing ……………….

………………. first introduced the electrochemical battery

An instrument to measure electrical power consumed is ……………….

Unit of electrical energy is ……………….

………………. is an instrument to measure the potential difference.

State principle of a potentiometer?

What is a thermistor?

What is a thermopile? On what principle does it work?

What is meant by the thermoelectric effect?

What is Joule’s heating effect?

(a) If both assertion and reason are true and the reason in the correct explanation of the assertion.
(b) If both assertion and reason are true but the reason is not correct explanation of the assertion.
(c) If assertion is true but reason is false.
(d) If the assertion and reason both are false.
(e) If assertion is false but reason is true.
Assertion: Electric appliances with metallic body e.g. heaters, presses, etc, have three pin connections, whereas an electric bulb has two pins.
Reason: Three pin connection reduce heating of connecting cables.

(a) If both assertion and reason are true and the reason in the correct explanation of the assertion.
(b) If both assertion and reason are true but the reason is not correct explanation of the assertion.
(c) If assertion is true but reason is false.
(d) If the assertion and reason both are false.
(e) If assertion is false but reason is true.
Assertion: In practical application, power rating of resistance is not important.
Reason: Property of resistance remains same even at high temperature

(a) If both assertion and reason are true and the reason in the correct explanation of the assertion.
(b) If both assertion and reason are true but the reason is not correct explanation of the assertion.
(c) If assertion is true but reason is false.
(d) If the assertion and reason both are false.
(e) If assertion is false but reason is true.
Assertion: Fuse wire must have high resistance and low melting point.
Reason: Fuse is used for small current flow only

Find the value of current I in the circuit shown in figure.

Explain the effective internal resistance of cells connected in parallel combination. Compare the results to the external resistance.

Explain the effective internal resistance of cells connected in series combination. Compare the results to the external resistance.

Explain in details of the temperature dependence of resistivity.

Explain the concept of colour code for carbon resistors.