# BASIC ELECTRONICS Test 11

Paper: Physics      Class: 10                    Time Allowed:    One Hour                           Marks: 25

Q1. Circle the correct answer.  (10)

1.The phenomenon of production of induced current in one coil due to change of current in a neighbouring coil is called:
a) electromagnetic induction              b) electrostatic induction               c) mutual induction                d) self induction
2.Which statement is true about the magnetic poles?
a) unlike pole repel                              b) like pole attract                                                                                                             c) magnetic poles do not effect each other                d) a single magnetic pole does not exist
3.Which rule is used to find direction of the force on a current carrying wire in a magnetic field?
a) right hand rule              b) Fleming’s left hand rule           c) head to tail rule             d) Hero’s formula
4.The lines of force of a coil are directed……………to its plane.
a) parallel            b) anti parallel              c) perpendicular              d) inclinde
5.Who found the direction of induced e.m.f. first time?
a) lenz           b) henry            c) newton            d) bohar
6.In a practical electric motor, the coil is called:
a) armature             b) coil                c) electromagnet               d) all of these
7.Transfer is used to change the value of:
a) Voltage            b) power                 c) Energy               d) Potential
8.If we increase the number of loops,the turning effect:
a) increase slightly            b) increase greatly              c) decrease suddenly             d) remains same
9.The direction of magnetic lines of force can be determined by:
a) left hand rule           b) right hand rule            c) head to tail rule          d) None of these
10.Which of the following have two coils, primary and secondary?
a) transformer            b) ac generator              c) dc motor             d) none of these

Q2. Write short answers to these questions: (15)
1.State Fleming’s left hand rule.
2.What is relay? How it works?
3.What is transformer?
4.What is the function of split Rings in the D.c motor.
5.What is a electromagnet?