MODULE 3 CHAPTER 3 QUIZ 3

Question Number. 21. A shunt is used with.

Option A. an ammeter. Option B. a voltmeter.

Option C. an ohmmeter.

Correct Answer is. an ammeter.

Explanation. A shunt is used to change the working range of an ammeter, by 'shunting' around the ammeter, a major portion of the current being measured ..................................

Question Number. 22. If a load in series has a current passing through it, the magnetic field can be worked out by using.

Option A. the corkscrew rule.

Option B. left hand rule.

Option C. right hand rule.

Correct Answer is. the corkscrew rule.

Explanation. NIL ..................................

Question Number. 23. The unit for power is.

Option A. Joules per second. Option B. N/m.

Option C. Volts/Amps. Correct Answer is. Joules per second.

Explanation. Power = energy (joules) / time (seconds) ..................................

Question Number. 24. In conventional flow, the left hand rule applies to.

Option A. generators.

Option B. batteries.

Option C. motors.

Correct Answer is. motors.

Explanation. Remember MG - the British car manufacturers (MG left to right) - or remember geneRIGHTer ..................................

Question Number. 25. When a conductor is cut by magnetic lines of force an EMF is induced. This is. Option A. Lenz's Law. ...

Option B. Faraday's Law.

Option C. Kirchhoff's Law.

Correct Answer is. Faraday's Law.

Explanation. NIL .................................

.Question Number. 26. The Watt can be expressed as.

Option A. Seconds per Joule. Option B. Joules * seconds.

Option C. Joules per second.

Correct Answer is. Joules per second. Explanation. Power = Energy(J) / Time(s) ..................................

Question Number. 27. The symbol for flux density is.

Option A. B. Option B. H.

Option C. MMF.

Correct Answer is. B. Explanation. NIL ..................................

Question Number. 28. To determine the direction of the magnetic field around a conductor you would use.

Option A. Fleming's right hand rule.

Option B. Fleming's left hand rule.

Option C. the corkscrew rule.

Correct Answer is. the corkscrew rule.

Explanation. NIL ..................................

Question Number. 29. Switching on or off the current in one coil produces an emf in another coil adjacent to it. The two coils are said to have.

Option A. self inductance.

Option B. auto inductance.

Option C. mutual inductance. Correct Answer is. mutual inductance.

Explanation. NIL ..................................

Question Number. 30. Self induced emf in a coil supplied with a current varying at a uniform rate can be found by.

Option A. -L dØ / dt

Option B. -N dI / dt Option C. -L dI / dt

Correct Answer is. -L dI / dt. Explanation. NIL. ...