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 voltage read by the volt meter is |
3V 2.8 V 3.2 V 3.4 V |
3.2 V |
$ 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$ $ R_{eq} = \frac{100\times 400}{500} = 80\Omega$ $ \text{Voltmeter reading } = 80\times 0.04 = 3.2V$ |