Class 12th Physics 2017 Set1 Delhi Board Paper Solution
(i) Find the value of the phase difference between the current and the voltage in the series L-C-R circuit shown below. Which one leads in phase : current or voltage?
(ii) Without making any other change, find the value of the additional capacitorC1 , to be connected in parallel with the capacitor C, in order to make the power factor of the circuit unity.
Therefore, current is leading in phase by a phase angle 135º.
Popular Questions of Class 12th physics
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A point charge of 2.0 μC is at the centre of a cubic Gaussian surface 9.0 cm on edge. What is the net electric flux through the surface?
Recently Viewed Questions of Class 12th physics
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A polythene piece rubbed with wool is found to have a negative charge of 3 × 10−7 C.
(a) Estimate the number of electrons transferred (from which to which?)
(b) Is there a transfer of mass from wool to polythene?
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(a) Two insulated charged copper spheres A and B have their centers separated by a distance of 50 cm. What is the mutual force of electrostatic repulsion if the charge on each is 6.5 × 10−7 C? The radii of A and B are negligible compared to the distance of separation.
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(b) in the outer region of the second plate, and
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A parallel plate capacitor with air between the plates has a capacitance of 8 pF (1pF = 10-12 F). What will be the capacitance if the distance between the plates is reduced by half, and the space between them is filled with a substance of dielectric constant 6?