 # Entry Test MCQ :: Electromagnetism

1.  Magnetic force acting on a unit positive charge moving perpendicular to the magnetic field with a unit velocity is called
 A. magnetic flux B. magnetic field intensity C. magnetic induction D. self inductance

2.  A current carrying conductor is placed in a uniform magnetic field parallel to it. The magnetic force experienced by the conductor is
 A. F=1/B B. F=1/Bsin? C. F/0 D. F=1/Bcos?

3.  What is the value of the current in a wire of 10cm long at the right angle to a uniform magnetic field of 0.5 Weber/m2 when the force acting on the wire is 5N?
 A. 1A B. 10A C. 100A D. 1000A

4.  When a particle of charge q and mass m enters into a uniform magnetic field B moving with a velocity v perpendicular to the direction for the field it describes a circular path of radius
 A. R=qB/mV B. R=mV/qB C. R=qmV/B D. R=qmB/V

5.  When a particle of charge q and mass m enters the uniform magnetic field B moving with velocity v perpendicular to the direction of the field the time required by a charged particle to make a complete revolution in a magnetic field is given by
 A. T=

6.  Two parallel wires carrying currents in the opposite directions
 A. repel each other B. attract each other C. have no effect upon each other D. they cancel out their individual magnetic fields

7.  A magnetic compass will be deflected if it is kept near a
 A. charge in motion B. charge at rest C. both D. none

8.  A magnetic field
 A. always exerts a force on a charged particle B. never exerts a force on a charged particles C. exerts a force if the charged particle is moving in the direction of the magnetic field lines D. exerts a force if the charged particle is moving perpendicular to the magnetic field lines

9.  A moving coil galvanometer of resistance 100? gives half scale deflection for a current of 20mA. What will be the potential difference across it?
 A. 4 volt B. 5 volt C. 2 volt D. 0.4 volt

10.  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