In a nuclear reactor, the number of U²³⁵ nuclei undergoing fissions per second is 4×10²⁰. If the energy released per fission is 250 MeV, then the total energy released in 10 h is (1 eV=1.6×10⁻¹⁹ […]
A total charge of 5µC is distributed uniformly on the surface of the thin walled semispherical cup. If the electric field strength at the centre of the hemisphere is 9×10⁸NC⁻¹, then the radius of the […]
A parallel plate capacitor has 91 plates, all are identical and arranged with same spacing between them. If the capacitance between adjacent plates is 3pF. What will be the resultant capacitance?
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(a) […]
When a light beam of frequency v is incident on a metal surface, photoelectrons are emitted. If these electrons describe a circle of radius r in a magnetic field of strength B, then the work […]
The range of voltmeter is 10V and its internal resistance is 50Ω. To convert it to a voltmeter of range 15V, how much resistance is to be added?
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(a) Add 25Ω resistor is […]
The electric current in AC circuit is given by the relation i-3 sinωt+4 cosωt. The rms value of the current in the circuit in ampere is
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(a) 5/√2 (b) 5√2 (c) √2/5 (d) […]
A rectangular copper coil is placed in a uniform magnetic field of induction 40 mT with its plane perpendicular to the field. The area of the coil is shrinking at a constant rate of 0.5 […]
A Gaussian surface in the cylinder of cross-section πa² and length L is immersed in a uniform electric field E with the cylinder axis parallel to the field.The flux ? of the electric field through […]
A 1Ω resistance in series with an ammeter is balanced by 75 cm of potentiometer wire. A standard cell of emf 1.02 V is balanced by 50 cm. The ammeter shows a reading of 1.5A. […]
A plane wave of wavelength 6250Å is incident normally on a slit of width 2×10⁻² cm. The width of the principal maximum of diffraction pattern on a screen at a distance of 50cm will be […]
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