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In an AC circuit the emf `(e)` and the current `(i)` at any instant are given respectively by, `e =E_0 sin omega t and i = I_0 sin (omegat-phi)` The average power in the circuit over one cycle of AC

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A transformer with turns ratio `N_1/N_2=50/1` is connected to a `120 V' 'AC` supply. If primary and secondary circuit resistances are `1.5 kOmega and 1Omega` respectively, then find out power of

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In an L-C-R series circuit, the voltage across each of the components L, C and R is 100 V. The voltage across the LC combination will

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Assertion: Inductive reactance of an inductor in DC circuit is zero. Reason: Angular frequency of DC circuit is

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Electrical ResonanceElectrical resonance is said to take place in a series L-C-R circuit when the circuit allows maximum current for a given frequency of the source of alternating supply for which capacitive reactance becomes equal to the inductive reactance. Impedance of this L-C-R circuit is minimum and hence current is maximum. Resonant circuits are used to respond selectively to signals of a given frequency while discriminating against signals of different frequencies. If the response of the circuit is more narrowly peaked around the chosen frequency, we say that the circuit has higher “selectivity or sharpness”. This sharpness is measures with

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Electrical ResonanceElectrical resonance is said to take place in a series L-C-R circuit when the circuit allows maximum current for a given frequency of the source of alternating supply for which capacitive reactance becomes equal to the inductive reactance. Impedance of this L-C-R circuit is minimum and hence current is maximum. Resonant circuits are used to respond selectively to signals of a given frequency while discriminating against signals of different frequencies. If the response of the circuit is more narrowly peaked around the chosen frequency, we say that the circuit has higher “selectivity or sharpness”. This sharpness is measures with

asked Mar 20, 2022 in 12th Physics by varun (6.7k points)

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L-C Oscillations When a capacitor is supplied with an AC circuit, it gets charged.When this charged capacitor is connected with an inductor, current flows through inductor, giving rise to magnetic flux. Hence, induced emf is produced in the circuit. Due to this, the charge on the capacitor decreases and an equivalent amount of energy is stored in the inductor in the form of magnetic Field.A capacitor of `1muF` is charged with 0.01C of charge. The energy stored in it

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AC Generator An AC generator produces electrical energy from mechanical work, just the opposite of what a motor does. In it, a shaft is rotated by some mechanical means, such as an engine or a turbine starts working and an emf is induced in the coil.It is based on the phenomenon of electromagnetic induction which states that whenever magnetic flux linked with a conductor (or coil) changes, an emf is induced in the coil. When the coil is rotated with a constant angular speed `omega`, then the angle `theta` between the magnetic field vector B and the area vector `A`

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A magician during a show makes a glass lens with n = 1.47 disappear in a trough of liquid. What is the refractive index of the liquid? Could the liquid be

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A convex lens has 20 cm focal length in air. What is focal length in water? (Refractive index of air-water = 1.33, refractive index for air-glass =

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An object of size 3.0cm is placed 14cm in front of a concave lens of focal length 21cm. Describe the image produced by the lens. What happens if the object is moved further away from the

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A compound microscope consists of an objective lens of focal length 2.0cm and an eyepiece of focal length 6.25cm separated by a distance of 15cm. How far from the objective should an object be placed in order to obtain the final image at the least distance of distinct vision

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Use the mirror equation to deduce that: a convex mirror always produces a virtual image independent of the location of the

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A small telescope has an objective lens of focal length 140cm and an eyepiece of focal length 5.0cm. What is the magnifying power of the telescope for viewing distant objects when (i)For the telescope described in Exercise 34 (a), what is the separation between the objective lens and the

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A glass lens of refractive index 1.45 disappears when immersed in a liquid. What is the value of refractive index of the

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The following table gives the values of the angle of deviation for different values of the angle of incidence for a triangular prism. Angle of incidence 33° 38° 42° 52° `60^o` 71° Angle of deviation O') `60^o` 50° 46° `40^o` 43° 50° (i) For what value of the angle of incidence, is the angle of emergence likely to be equal to the angle of incidence itself? (ii) Draw a ray diagram showing the passage of a ray of light through this prism when the angle of incidence has the above

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A converging lens has a focal length of 20 cm in air. It is made of a material of refractive index 1.6. It is immersed in a liquid of refractive index 1.3. Calculate its new focal

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The image obtained with a convex lens is erect and its length is four times the length of the object. If the focal length of the lens is 20 cm, calculate the object and image

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An object of 3 cm height is placed at a distance of 60 cm from a convex mirror of focal length 30 cm. Find the nature, position and size of the image

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A myopic adult has a far point at 0.1 m. His power of accomodation is 4 diopters. What is his near point without

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