Page 715 - SUBSEC October 2017_Neat
P. 715

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                           (ii)    State what is meant by the bandwidth of an amplifier.
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                           (iii)    Explain the use of logarithmic scales on the vertical and horizontal axes.


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                    (c)     Draw tangents to the graph at the points (log f  = 2.0, log A = 2.0) and (log f =
                                                                                  10
                                                                                                    10
                                                                      10
                           4.8, log A = 1.54) and produce them to find the point at which they intersect.
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                    (d)    The point of intersection of the tangents gives the bandwidth of the amplifier.


                           (i)     Determine the bandwidth of this amplifier.

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                                   (ii)     Calculate the resulting bandwidth of the amplifier if the input resistor was
                                  changed to 1 kΩ.
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