The term liquid crystal refers to a state that is intermediate between
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(a) Crystalline solid and amorphous liquid (b) Crystalline solid and vapour (c) Amorphous liquid and its vapour (d) A crystal […]
In a transistor the collector current is always less than the emitter current because
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(a) Collector side is reverse biased and the emitter side is forward biased (b) A few electrons are […]
Maximum velocity of the photoelectrons emitted by a metal surface is 1.2×10⁶ ms⁻¹. Assuming the specific charge of the electron to be 1.8×10¹¹ C kg⁻¹, the value of the stopping potential in volt will be […]
When light of wavelength 300 nm falls on a photoelectric emitter, photoelectrons are liberated. For another emitter, light of wavelength 600 nm is sufficient for liberating photoelectrons. The ratio of the work function of the […]
The electron drift speed is small and the change of the electron is also small but still, we obtain large current in a conductor. This is due
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(a) the conducting property of […]
If λ₁ and λ₂ are the wavelengths of the first members of the Lyman and Paschen series respectively, then the λ₁ : λ₂ is
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(a) (1:3) (b) (1:30) (c) (7:50) (d) (7:108)
In a LCR series circuit, the potential difference between the terminals of the inductor is 60 V, between the terminals of the capacitor is 30 V and that across the resistance is 40 V. Then, […]
Activity of a radioactive sample decreases to (1/3)rd of its original value in 3 days. Then, in 9 days its activity will become
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(a) (1/27) of the original value (b) (1/9) of […]
A battery of emf 10 V and internal resistance 3 ohm is connected to a resistor. The current in the circuit is 0.5 A. The terminal voltage of the battery when the circuit is closed […]
A Carnot engine takes heat from a reservoir at 627⁰C and rejects heat to a sink at 27⁰C. Its efficiency will be
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(a) (3/5) (b) (1/3) (c) (2/3) (d) (200/209)
Correct Answer: […]
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