EASY
NDA & NA EE
IMPORTANT
Earn 100

Assertion (A): As soon as a source of emf is connected across a conductor, a current immediately starts flowing through it.
Reason (R): Drift speed of the electron is so large that electron travel from one end of the conductor to the other end almost instantaneously.

33.33% studentsanswered this correctly

Important Questions on Current Electricity

EASY
NDA & NA EE
IMPORTANT
Physics Crash Course NDA & NA EE>Chapter 18 - Current Electricity>Exercise 1>Q 15
There are 8.4×1022 free electrons per cm3 in copper. The current in the wire is 0.21 A e=1.6×10-19 C. Then the drift velocity of electrons in a copper wire of 1 mm2 cross-section, will be:
EASY
NDA & NA EE
IMPORTANT
Physics Crash Course NDA & NA EE>Chapter 18 - Current Electricity>Exercise 1>Q 16
In current electricity, Ohm's law is obeyed by all _____.
EASY
NDA & NA EE
IMPORTANT
Physics Crash Course NDA & NA EE>Chapter 18 - Current Electricity>Exercise 1>Q 17

In the circuit shown below, a student performing Ohm's law experiment accidentally puts the voltmeter and the ammeter as shown in the circuit below; the reading in the voltmeter will be close to
Question Image

EASY
NDA & NA EE
IMPORTANT
Physics Crash Course NDA & NA EE>Chapter 18 - Current Electricity>Exercise 1>Q 18
Current flowing through a circuit is shown in the figure then the resistance of the circuit is
Question Image
EASY
NDA & NA EE
IMPORTANT
Physics Crash Course NDA & NA EE>Chapter 18 - Current Electricity>Exercise 1>Q 19
Which one of the following devices is non-ohmic?
EASY
NDA & NA EE
IMPORTANT
Physics Crash Course NDA & NA EE>Chapter 18 - Current Electricity>Exercise 1>Q 20
A potential difference of 5 V is applied across a conductor of length 0.1 m. If the electron mobility is 5×10-6 m2v-1s-1 then the drift velocity of electron is
EASY
NDA & NA EE
IMPORTANT
Physics Crash Course NDA & NA EE>Chapter 18 - Current Electricity>Exercise 1>Q 21
A copper wire of length 1 m and uniform cross-sectional area 5×10-7 m2 carries a current of 1 A. Assuming that there are 8×1028 free electrons per m3 in copper, how long will an electron take to drift from one end of the wire to the other?
EASY
NDA & NA EE
IMPORTANT
Physics Crash Course NDA & NA EE>Chapter 18 - Current Electricity>Exercise 1>Q 22
Drift velocity of electrons in a wire of a certain length and the circular cross-section is, Vd.. The potential difference across the wire and the wire length is doubled but, the radius of the cross-section is halved. What is the new drift speed?