For a normal eye, the cornea of eye provides a converging power 40 D and the least converging power of the eye lens behind the cornea is 20 D. Using this information, the distance between […]
A wave travelling in the +ve x-direction having displacement along y-direction as 1m, wavelength 2π and frequency 1 /π Hz is represented by
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(a) y = sin ( 2 πx – 2 […]
A source of unknown frequency gives 4 beats/s, when sounded with a source harmonic of the source of unknown frequency gives 5 beats/s, when sounded with a source of frequency 513 Hz. The unknown frequency […]
If we study the vibration of a pipe open at both ends, then which of the following statements is not true?
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(a) Odd harmonies of the fundamental frequency will be generated (b) […]
A parallel beam of fast moving electrons is incident normally on a narrow slit. A flourescent screen is placed at a large distance from the slit. If the speed of the electrons is increased, then […]
During an adiabatic process, the pressure of a gas is found to be proportional to the cube of its temperature. The ratio of Cp/Cv for the gas is
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(a) 2 (b) 5/3 […]
In a common emitter (CE) amplifier having a voltage gain G, the transistor used has transconductance 0.03 mho and current gain 25. If the above transistor is replaced with another one with transconductance 0.02 mho […]
In a n-type semiconductor, which of the following statement is true?
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(a) Electrons and minority carriers and pentavalent atoms are dopants (b) Holes and minotiry carriers and pentavalent atoms are dopants (c) […]
The wavelength λₑ of an electron and λₚ of a photon are of same energy E are related by
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(a) λₚ ∞ λₑ (b) λₚ ∞ √λₑ (c) λₚ ∞ 1/√λₑ (d) […]
For photoelectric emission from certain metal the cut-off frequency is v. If radiation of frequency 2v impinges on the metal plate, the maximum possible velocity of the emitted electron will be (m is the electron […]
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