Explore topic-wise MCQs in Electronics.

This section includes 110 Mcqs, each offering curated multiple-choice questions to sharpen your Electronics knowledge and support exam preparation. Choose a topic below to get started.

101.

The ability of a material to maintain a magnetized state (without the presence of a magnetizing force) is called hysteresis.

A. 1
B.
Answer» C.
Discussion
102.

The Hall voltage is the voltage created by a conductor moving through a magnetic field.

A. 1
B.
Answer» C.
Discussion
103.

The movable part in a relay is the _____.

A. plunger
B. armature
C. cone
D. brushes
Answer» C. cone
Discussion
104.

The ability of a material to maintain a magnetized state (without the presence of a magnetizing force) is called retentivity.

A. 1
B.
Answer» B.
Discussion
105.

The flux density is ___ when the magnetic flux is 9 µWb and the cross-sectional area of the magnetic field is 5 × 10–3 m2.

A. 1800 µT
B. 555.56 T
C. 9 µT
D. 5 × 10–3 T
Answer» B. 555.56 T
Discussion
106.

When the current through a coil reverses direction, the magnetic field around the coil _____.

A. does not change
B. disappears
C. increases in strength
D. reverses direction
Answer» E.
Discussion
107.

The Hall effect

A. is a phenomenon with no practical applications
B. is used in various sensor applications
C. can develop potentials of thousands of volts
D. is the basis for solar cell operation
Answer» C. can develop potentials of thousands of volts
Discussion
108.

The unit of magnetic flux density is the weber.

A. 1
B.
C. 1
D.
Answer» C. 1
Discussion
109.

How much flux is there in a magnetic field when its flux density is 5000 T and its cross-sectional area is 300 mm2?

A. 16.67 mWb
B. 5.0 Wb
C. 3.0 mWb
D. 1.5 Wb
Answer» E.
Discussion
110.

What is the flux density of a magnetic field whose flux is 3000 µWb and cross-sectional area is 0.25 m2?

A. 12,000 T
B. 83,330 T
C. 0 T
D. More information is needed in order to find flux density.
Answer» B. 83,330 T
Discussion