Current Electricity and Electrical InstrumentHard
Question
In the circuit shown, reading of the voltmeter connected across 400 Ω resistance is 30 V. If it is connected across 300 Ω resistance then reading will be
Options
A.45 V
B.32.5 V
C.22.5 V
D.18 V
Solution
Case - I 
current I =
amp I1 = 
amp
30 = (I - I1)RV ⇒ RV =
= 1200Ω
Case = II
I =
= 
amp.
I0 300 = (I − I0) 1200 ⇒ I0 =
I = 
amp
Reading of voltmeter
× 300 = 
= 22.5 V
current I =
amp I1 = amp30 = (I - I1)RV ⇒ RV =
= 1200ΩCase = II
I =
= amp.I0 300 = (I − I0) 1200 ⇒ I0 =
I = ampReading of voltmeter
× 300 = = 22.5 VCreate a free account to view solution
View Solution FreeTopic: Current Electricity and Electrical Instrument·Practice all Current Electricity and Electrical Instrument questions
More Current Electricity and Electrical Instrument Questions
Current sensitivity of a moving coil galvanometer is 5 div/mA and its voltage sensitivity (angular deflection per unit v...Two identical batteries, each of emf 2V and internal resistance r = 1Ω are connected as shown. The maximum powe...A potential difference V is applied across a copper wire of diameter d and length L. when only d is doubled, the drift v...A resistance of 4 Ω and a wire of length 5 m and resistance 5Ω are joined in series and connected to a cell of...Two stones are thrown up simultaneously from the edge of a cliff 240 m high with initial speed of 10 m/s and 40 m/s resp...