When the coil of a galvanometer settles in equilibrium, how does the deflecting couple compare with the restoring couple?
Correct answer C. It equals the restoring couple
Topic / 897 questions
Physics MCQs
Page 31 of Physics multiple-choice questions with answers. Tap an option to check yourself.
Page 31 of 45
Which instrument can measure potential difference without drawing any current?
Correct answer D. Cathode ray oscilloscope (CRO)
An electron enters a region where an electric field E is perpendicular to a magnetic field B. Under what condition does it pass through undeflected?
Correct answer B. E = Bv
Advertisement
Which symbol is conventionally used for the magnetic flux density vector?
Correct answer D. B
What is the SI unit of magnetic flux density?
Correct answer B. N A⁻¹ m⁻¹
How is the tesla related to the smaller unit of magnetic induction, the gauss?
Correct answer C. 1 T = 10⁴ G
Which material is best suited for the core of an electromagnet?
Correct answer A. Soft iron
Which statement about a magnetic field and a charged particle is correct?
Correct answer A. It exerts a force if the charged particle is moving perpendicular to the magnetic field lines
What happens to two parallel wires carrying currents in opposite directions?
Correct answer C. They repel each other
Advertisement
A 10 cm wire lies at right angles to a uniform magnetic field of 0.5 Wb/m², and the force on it is 5 N. What current flows in the wire?
Correct answer B. 100 A
What is the magnetic force on a unit positive charge moving at unit velocity perpendicular to a magnetic field called?
Correct answer D. Magnetic induction
What is the overall charge on an n-type semiconductor?
Correct answer C. Neutral
What are the charge carriers in a semiconductor?
Correct answer B. Both electrons and holes
In which type of material can holes exist?
Correct answer C. Semiconductors
Many semiconductors crystallise in which type of structure?
Correct answer C. Face centred cubic
Advertisement
What are electrons in the conduction band free to do?
Correct answer C. Transport charge
What is an empty or partially filled energy band called?
Correct answer C. Conduction band
In a simple cubic unit cell, where are the atoms or molecules located?
Correct answer B. Eight corners
What is the breaking of a crystal along definite directions called?
Correct answer C. Cleavage
Bulk properties of materials, such as the way they fracture, can be related to their what?
Correct answer B. Microstructure