Practicing Success
Answer the following questions relating to the adjoining circuit diagram. When the voltmeter is connected across the 100W resistance the ammeter reading is 0.04 amp. |
The resistance of the voltmeter is |
$800\Omega$
$1200\Omega$ $1600\Omega$ $400\Omega$ |
$400\Omega$ |
$ I = \frac{3.4}{3+2+ 100R_v/100+R_v} = 0.04$ $ \frac{100R_v}{100+R_v} + 5 = 85$ $ \Rightarrow \frac{100R_v}{100+R_v} = 80$ $ \Rightarrow 5R_v = 400 + 4R_v $ $ R_v = 400\Omega$
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