131. Which one of the following material is most suitable for making core of an electromagnet?
A. Air
B. Steel
C. Cu-Ni alloy
D. Soft iron
✅ The correct answer is option D.
Physics MCQs
Prepare effectively with our Physics MCQs with answers and explanations for exams and job tests. Our collection covers key topics such as mechanics, thermodynamics, optics, electricity and magnetism, modern physics, waves, and quantum theory. These multiple-choice questions are designed for students, competitive exam aspirants, and professionals preparing for NTS, PPSC, FPSC, CSS, PMS, university entry tests, and physics-related job assessments. Practice online to strengthen your concepts, improve problem-solving skills, and excel in exams with our updated Physics MCQs
132. Emf generated by A.C dynamo depends upon
A. Number of turns in the coil
B. Magnetic field strength
C. Frequency of rotation
D. All of above
✅ The correct answer is option D.
133. A changing magnetic flux produces around itself an induced
A. Magnetic field
B. Electric field
C. Electromagnetic force
D. Artificial gravitational field
✅ The correct answer is option C.
134. An alternating current or voltage
A. Fluctuates off and on
B. Varies in magnitude alone
C. Changes its direction again and again
D. Changes its magnitude harmonically and reverses its direction of flow after regularly recurring intervals.
✅ The correct answer is option C.
135. Maxwell derived mathematically that the velocity of the electromagnetic waves is
A. 3.00 x 108 m/s
B. 3.00 x 10 m/s
C. 300 x 108 m/s
D. 3.00 x 8 m/s
✅ The correct answer is option B.
136. The current through a metallic conductor is due to the motion of
A. Free Electrons
B. Protons
C. Neutrons
D. Still under controversy
✅ The correct answer is option A.
137. A dynamo converts
A. Mechanical energy into electrical energy
B. Electrical energy into mechanical energy
C. Magnetic energy into mechanical energy
D. Magnetic energy into electrical energy
✅ The correct answer is option A.
138. Electromagnetic waves travel in free space with the speed of
A. λ-rays
B. Positive rays
C. Cathode rays
D. More than sound waves
✅ The correct answer is option A.
139. The resistance of a conductor depends upon
A. Nature of the conductor
B. The dimension of the conductor
C. The physical state of the conductor
D. All of above
✅ The correct answer is option D.
140. Which one of the following functions like a motor?
A. Galvanometer
B. Ammeter
C. Voltmeter
D. All of above
✅ The correct answer is option D.