[{"id":166355,"question":"The step-up transformer","choices":[{"text":"Increases the input current","value":"A"},{"text":"Increase the input voltage","value":"B"},{"text":"Has more turns in the primary","value":"C"},{"text":"Has less turns in hte secondary coil","value":"D"},{"value":"E"}],"correctAnswer":2},{"id":166354,"question":"The direction of induced e.m.f. in a circuit is in accordance with conservation of.","choices":[{"text":"Mass","value":"A"},{"text":"Charge","value":"B"},{"text":"Momentum","value":"C"},{"text":"Energy","value":"D"},{"value":"E"}],"correctAnswer":4},{"id":166353,"question":"Which part of a D.C. motor reverses the direction of current through the coil every half-cycle.","choices":[{"text":"The armature","value":"A"},{"text":"The commutator","value":"B"},{"text":"The burshes","value":"C"},{"text":"The slip rings","value":"D"},{"value":"E"}],"correctAnswer":4},{"id":166352,"question":"D.C. motor converts.","choices":[{"text":"Mechanical energy into electrical energy","value":"A"},{"text":"Mechanical energy into chemical energy","value":"B"},{"text":"Electrical energy into mechanical energy","value":"C"},{"text":"Electrical energy into chemical energy","value":"D"},{"value":"E"}],"correctAnswer":3},{"id":166351,"question":"If the current in a wire which is placed perpendicular to a magnetic field increases, the force on the wire.","choices":[{"text":"Increases","value":"A"},{"text":"Decreases","value":"B"},{"text":"Remains the same","value":"C"},{"text":"Will be zero","value":"D"},{"value":"E"}],"correctAnswer":1},{"id":166350,"question":"The presence of a magnetic field can be detected by a","choices":[{"text":"small mass","value":"A"},{"text":"Stationary positive charge","value":"B"},{"text":"Stationary negative charge","value":"C"},{"text":"Magnetic compass","value":"D"},{"value":"E"}],"correctAnswer":4},{"id":166349,"question":"What is the direction of the magnetic field lines inside a bar magnet?","choices":[{"text":"From north pole to south pole","value":"A"},{"text":"From south pole to north pole","value":"B"},{"text":"From side to side","value":"C"},{"text":"There are no magnetic field lines.","value":"D"},{"value":"E"}],"correctAnswer":2},{"id":166348,"question":"Which statement is true about the magnetic poles?","choices":[{"text":"Unlike poles repel","value":"A"},{"text":"Like poles attract","value":"B"},{"text":"Magnetic poles do not effect each other","value":"C"},{"text":"A single magnetic pole does not exist","value":"D"},{"value":"E"}],"correctAnswer":4},{"id":40535,"question":"Transformer works on _______ supply.","choices":[{"text":"A.C","value":"A"},{"text":"D.C","value":"B"},{"text":"Battery","value":"C"},{"text":"Both A and B","value":"D"},{"value":"E"}],"correctAnswer":1},{"id":40534,"question":"A transformer has 100 turns in its primary and 500 turns in secondary coil. If 6 volts D.C is applied across its primary, the voltage induced across its secondary coil will be:","choices":[{"text":"0 volt","value":"A"},{"text":"30 volts","value":"B"},{"text":"45 volts","value":"C"},{"text":"60 volts","value":"D"},{"value":"E"}],"correctAnswer":1},{"id":40533,"question":"The coil of a transformer which is connected to A.C is called:","choices":[{"text":"Primary coil","value":"A"},{"text":"Secondary coil","value":"B"},{"text":"Field coil","value":"C"},{"text":"Armature coil","value":"D"},{"value":"E"}],"correctAnswer":1},{"id":40532,"question":"Which device is used to increases / decreases A.C Voltage?","choices":[{"text":"Electric motor","value":"A"},{"text":"Transformer","value":"B"},{"text":"A.C Generator","value":"C"},{"text":"Solenoid","value":"D"},{"value":"E"}],"correctAnswer":2}]