When photons of energy hν fall on an aluminium plate (of work function E₀), photoelectrons of maximum kinetic energy K are ejected. If the frequency of radiation is doubled, the maximum kinetic energy of the […]
Cathode rays are produced when the pressure is of the order of
Options
(a) 2 cm of Hg (b) 0.1 cm of Hg (c) 0.01 mm of Hg (d) 1μm of Hg
Correct […]
A battery of e.m.f. E and internal resistance r is connected to an external resistance R the condition for maximum power transfer is
Options
(a) rR (c) r=1/R (d) r=R
Correct Answer:
r=R
A galvanometer having internal resistance 10Ω requires 0.01 A for a full scale deflection. To convert this galvanometer to a voltmeter of full scale deflection at 120V, we need to connect a resistance of
Ratio of longest wavelengths corresponding to Lyman and Balmer series in hydrogen spectrum is
Options
(a) (5/27) (b) (3/23) (c) (7/29) (d) (9/31)
Correct Answer:
(5/27)
Explanation:
No explanation available. Be the first […]
A nuclear reaction is given as 4 ₁H¹→₂He⁴+₀e¹+energy Mention the type of reaction.
Options
(a) fusion (b) fission (c) just a chemical reaction (d) None of these
Correct Answer:
fusion
Explanation:
No explanation […]
A L-C-R circuit with L=1.00 mH, C=10μF and R=50Ω, is driven with 5 V AC voltage. At resonance, the current through the circuit is
Options
(a) 0.2 A (b) 0.25 A (c) 0.15 […]
The difference in the lengths of a mean solar day and a sidereal day is about
Options
(a) 1 min (b) 4 min (c) 15 min (d) 56 min
Correct Answer:
56 min
Which of the following pairs is wrong
Options
(a) Pressure-Barometer (b) Relative density-Pyrometer (c) Temperature-Thermometer (d) Earth-Seismograph
Correct Answer:
Relative density-Pyrometer
Explanation:
Barometer – Used to measure a atmospheric pressure
Pyrometer – Used to […]
Two bodies A and B have masses 20 Kg and 5 Kg respectively. Each one is acted upon by a force of 4 kg wt. If they acquire the same kinetic energy in times tᴀ […]
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