Test 20 June

What is the unit of electric current?

Which of the following materials is a good conductor of electric current?

Ohm’s Law states that the current through a conductor between two points is directly proportional to which of the following?

If a resistor has a resistance of 10 ohms and a current of 2 amperes flows through it, what is the voltage across the resistor? (Write numerical value.)

In a series circuit with a total resistance of 100 ohms and a voltage supply of 50 volts, what is the current flowing through the circuit?

What is drift velocity?

Which formula correctly represents drift velocity (v_d ) in terms of current (I), number density (n), charge (e), and cross-sectional area (A)?

If the drift velocity of electrons in a copper wire is \(1 \times 10^{-4} \, \text{m/s} \) and the number density of free electrons is \(8.5 \times 10^{28} \, \text{m}^{-3}\), what is the current flowing through the wire with a cross-sectional area of \(1 \times 10^{-6} \, \text{m}^2\)? (Charge on electron, \(e = 1.6 \times 10^{-19} \, \text{C}\)).

How does the drift velocity change if the number density of charge carriers is doubled while keeping the current constant?

In a certain conductor, the drift velocity of electrons increases by a factor of 3 when the electric field is increased. What can be inferred about the relationship between drift velocity and electric field?