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Homework Help: Electronics Problem

  1. Apr 18, 2010 #1
    1. The problem statement, all variables and given/known data
    A 1N4737 zener diode has a 7.5 V zener voltage and is rated at 1 W power dissipation. It is
    to be used in the circuit shown at right to regulate the voltage to a small radio circuit which
    requires a constant voltage of 7.5 V. The supply voltage can vary between 9 V and 12 V.

    a. What is the maximum current that can pass through the diode without exceeding the
    power rating?
    b. What is the maximum current that can be drawn by the radio in this circuit?
    c. What is the minimum value of the dropping resistor, Rd, that can be used in this circuit?
    d. What could happen if a resistor of lower value was used?
    e. Why not use a higher value resistor?

    I dont get it at all. I need your help!

    I understand that part a is simply I=P/V which means current will be 0.13A

    2. Relevant equations
    P=VI V=IR P=V^2/R

    3. The attempt at a solution
    Dont even know where to start with part b.

    Attached Files:

  2. jcsd
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