The ratio of amplitude of magnetic field to the amplitude of electric field for an electromagnetic wave propagating in vacuum is equal to:
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(a) The speed of light in vacuum (b) reciprocal […]
Three masses are placed on the x-axis : 300 g at origin, 500 g at x = 40 cm and 400 g at x = 70 cm. The distance of the centre of mass from […]
A proton carrying 1 MeV kinetic energy is moving in a circular path of radius R in uniform magnetic field. What should be the energy of an α-particle to describe a circle of same radius […]
A magnetic needle suspended parallel to a magnetic field requires √3 J of work to turn it through 60⁰. The torque needed to maintain the needle in this position will be:
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(a) […]
If vₑ is escape velocity and v(o) is orbital velocity of a satellite for orbit close to the earth’s surface, then these are related by:
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(a) v(o) = √2 vₑ (b) v(o) […]
A train moving at a speed of 220 ms⁻¹ towards a stationary object, emits a sound of frequency 1000 Hz. Some of the sound reaching the object gets reflected back to the train as echo. […]
A parallel plate capacitor as a uniform electric field E in the space between the plates. If the distance between the plates is d and area of each plate is A, the energy stored in […]
Two metallic spheres of radii 1 cm and 3 cm are given charges of -1 x 10⁻² C and 5 x 10⁻² C, respectively. If these are connected by a conducting wire, the final charge […]
The input resistance of a silicon transistor is 100 W. Base current is changed by 40 µA which results in a change in collector current by 2mA. This transistor is used as a common emitter […]
Two radiations of photons energies 1 eV and 2.5 eV, successively illuminate a photosensitive metallic surface of work function 0.5 eV. The ratio of the maximum speeds of the emitted electrons is:
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