Electrical Exam Questions.

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1. What is the force on a conductor which carries 10 Amps in a magnetic field with a flux density of 0.8 Tesla? The effective length of the conductor is 300mm.


Answer = F=BLI, 


                     F = 0.8 X 0.3 X 10


                     F = 2.4 N.


2. The peak value of a sine wave is 350 Volts. Calculate:


i, The R.M.S. value.  Answer = 350 X 0.707

                                                       = 247.5 Volts.


ii, The average value of a half cycle. Answer = 350 X 0.636

                                                                                   = 222.6 Volts.

                                                                

iii, The peak to peak value. Answer = 350 X 2


                                                                  + 700 Volts.


                                                 


3. An A.C. generator runs at 15 revs per second. It produces an R.M.S. output of 240 Volts at 60 Hz. If the speed is increased to 20 revs/second, state the effect on:


i, The Voltage output. Answer = Voltage will increase.


ii, The frequency. Answer = Frequency will increase.


iii, The periodic time. Periodic time will decrease.


4, Who said, "If chain still swinging, seat is still warm? Answer = Benny Hill.


5. What is the modern name for what was historically called a "spur box?"


Answer = Fused connection unit.


6. A card has 5 Amp, 15 Amp and 30 Amp fuse wire on it. What is it made of?


Answer = Cardboard  or copper. Depending on which side of the river you come from.


Z.


 

Zoomup:

1. What is the force on a conductor which carries 10 Amps in a magnetic field with a flux density of 0.8 Tesla? The effective length of the conductor is 300mm.


Answer = F=BLI, 


                     F = 0.8 X 0.3 X 10


                     F = 2.4 N.


2. The peak value of a sine wave is 350 Volts. Calculate:


i, The R.M.S. value.  Answer = 350 X 0.707

                                                       = 247.5 Volts.


ii, The average value of a half cycle. Answer = 350 X 0.636

                                                                                   = 222.6 Volts.

                                                                

iii, The peak to peak value. Answer = 350 X 2


                                                                  + 700 Volts.


                                                 


3. An A.C. generator runs at 15 revs per second. It produces an R.M.S. output of 240 Volts at 60 Hz. If the speed is increased to 20 revs/second, state the effect on:


i, The Voltage output. Answer = Voltage will increase.


ii, The frequency. Answer = Frequency will increase.


iii, The periodic time. Periodic time will decrease.


4, Who said, "If chain still swinging, seat is still warm? Answer = Benny Hill.


5. What is the modern name for what was historically called a "spur box?"


Answer = Fused connection unit.


6. A card has 5 Amp, 15 Amp and 30 Amp fuse wire on it. What is it made of?


Answer = Cardboard  or copper. Depending on which side of the river you come from.


Z.