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A resistor R, an inductor L, a capacitor C and voltmeters V₁, V₂ and V₃ are connected to an oscillator in the circuit as shown in the adjoining diagram. When the frequency of the oscillation is increased, then at the resonant frequency, the voltmeter reading is zero in the case of

In the given circuit diagram, E = 5 V, r = 1 Ω, R₂ = 4 Ω, R₁ = R₃ = 1 Ω and C = 3 μF. Then, what will be the numerical value of charge on each plate of the capacitor?

A parallel plate capacitor with air between the plates has a capacitance of 9 pF. The separation between the plates is d. The space between the plates is now filled with two dielectrics: one has dielectric constant K₁ = 3 and thickness d/3, while the other has dielectric constant K₂ = 6 and thickness 2d/3. Capacitance of the capacitor is now

The resistance of a wire at 20°C is 20 Ω and at 500°C is 60 Ω. At which temperature will its resistance be 25 Ω?

In the circuit shown, the heat produced in the 5 Ω resistor is 10 cal s⁻¹. The heat produced per second in the 4 Ω resistor will be

In the given circuit, find X such that potential difference between B and D is zero.

To increase the current sensitivity of a moving coil galvanometer by 50%, its resistance is increased, so that new resistance becomes twice its initial resistance, by what factor does its voltage sensitivity change?

In the given circuit, it is observed that the current I is independent of the value of resistance R₅. Then, the resistance value must satisfy

A conducting circular loop is placed in a uniform magnetic field B = 0.025 T, with its plane perpendicular to the field. The radius of the loop is made to shrink at a constant rate of 1 mm s⁻¹. The induced emf when the radius is 2 cm is

Two inductors L₁ and L₂ are connected in parallel and a time-varying current flows as shown. The ratio of currents i₁/i₂ at any time is:

A copper rod of mass m slides under gravity on two smooth parallel rails l distance apart and set at an angle θ to the horizontal. At the bottom, the rails are joined by a resistance R as shown in figure. There is a uniform magnetic field B perpendicular to the plane of the rails. The terminal velocity of rod is

Two metal plates having a potential difference of 800 V are 2 cm apart. It is found that a particle of mass 1.96 × 10⁻¹⁵ kg remains suspended in the region between the plates. The charge on the particle must be (e = 1.6 × 10⁻¹⁹ C)