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Christmas Day Quiz.

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Test that your brain cells are still working after the Christmas Dinner and gallons of finest cooking sherry. The test......


Q.1. Which famous English scientist and mathematician was born on Christmas day in 1642?


Q.2. Which German electrical engineer and Nobel Prize winner was born on Christmas Day in 1906?


Q.3 When was the Queen's Christmas Message first televised (year)?


Q.4. What is the total end to end resistance at 20 degrees C, of the following single copper conductors assuming zero joint resistances.


25m 1.0mm2, + 50m 1.5mm2, + 75m 2.5mm2, + 20m 4.0mm2. (Ohms)


Q.5. According to the B.I.C.C. book "The Electrician's Mate", Third Edition about Mi cables, which London building has 21 miles of M.I. cable installed in it?


Q.6. According to the book referred to in Q.5 what is the life expectancy of copper  M.I.C.C. cable.


Q.7. According to the book referred to in Q.5 (a) what is the insulation used in M.I.C.C. cable? AND (b) does it age?


Z.




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  • 0
    1) Isaac Newton, gravity, planets and all that.

    2) Ernst August Friedrich Ruska was a German physicist who won the Nobel Prize in 1986 for his  design of the first electron microscope and related electron optics.

    3) 1957

    4)      25m 1.0mm2, = 18mohm*25 =0.45 ohms

    + 50m 1.5mm2, =12mohm*50 =0.6 ohms

    + 75m 2.5mm2, =7,2 mohm *75 =0.54 ohms

    + 20m 4.0mm2. (Ohms)  4.5mohm *20 = 0.09 ohms

    ==1.68 ohms

    Assuming 18 milliohms per mm2/m long. Pure copper will be a touch less.


    5) I do not have This book   on my shelf. I'dd imagine a famous one, like the palace or parliament.


    6) at least 100 years, well if it is the same as another book.


    7) Magnesium oxide == magnesia. Stable indefinitely, so long as you keep it dry.
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  • 0
    1) Isaac Newton, gravity, planets and all that.

    2) Ernst August Friedrich Ruska was a German physicist who won the Nobel Prize in 1986 for his  design of the first electron microscope and related electron optics.

    3) 1957

    4)      25m 1.0mm2, = 18mohm*25 =0.45 ohms

    + 50m 1.5mm2, =12mohm*50 =0.6 ohms

    + 75m 2.5mm2, =7,2 mohm *75 =0.54 ohms

    + 20m 4.0mm2. (Ohms)  4.5mohm *20 = 0.09 ohms

    ==1.68 ohms

    Assuming 18 milliohms per mm2/m long. Pure copper will be a touch less.


    5) I do not have This book   on my shelf. I'dd imagine a famous one, like the palace or parliament.


    6) at least 100 years, well if it is the same as another book.


    7) Magnesium oxide == magnesia. Stable indefinitely, so long as you keep it dry.
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