Current Electricity Question Paper CLASS 12TH

PATHAK’S ACADEMY SPECTRUM

TOPIC : Current Electricity         CLASS : 12^th    BOARD : STATE/CBSE

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Q1) State and explain Kirchhoff’s Voltage law.(2)

Q2) State any two advantages of Potentiometer over Voltmeter.(2)

Q3) A Voltmeter has resistance of 100 Ω.  What it will show when connected across the cell of emf 2V and internal resistance 20Ω ?(2)

Q4) Explain the principal of potentiometer with neat lablled diagram.(3)

Q5) Obtain the balancing condition for Wheatstone’s bridge Network with suitable diagram.(3)

Q6) A Cell with internal Resistance 2.5 Ω is balanced across 450 cm length of Potentiometer wire. The cell is shunted by a resistance of 4 Ω . Calculate the balancing length.(3)

Q7) Explain the use of potentiometer to compare the emfs of two cells bu sum and difference method. A Potentiometer wire has length of 2m and resistance 10 Ω  . It is connected in series with resistance 990Ω and a cell of emf 2V. Calculate the potential gradient along the wire. (4)

Q8) Explain with neat lablled diagram, how will you determine the unknown resistance by using Meter Bridge Experiment. The current flowing through the external resistance of 2Ω. is 0.5 A when it is connected to the terminal of a cell. The current reduces to 0.25 A when external resistance is 5Ω. Use Kirchoff law to find emf of cell. (4)

Q9) Four resistances 4Ω , 8Ω, XΩ ,6Ω  are connected in series so as to form Wheatston’s bridge Network. If the Network is balanced find the value of X. (2)