A capacitor of capacitance 100μF is charged by connecting it to a battery of voltage 12V with internal resistance 2Ω. The time after which 99% of the maximum charge is stored on the capacitor is […]
The parallel beams of monochromatic light of wavelength 4.5 x10⁻⁷ m passes through a long slit with width 0.2×10⁻³ m. The angular divergence in which most of the light is
Options
(a) 4.5×10⁻³rad […]
The velocity of image when object and mirror both are moving towards each other with velocities 4 ms⁻¹ and 5 ms⁻¹ respectively, is
Options
(a) (-14ms⁻¹) (b) 15ms⁻¹ (c) (-9ms⁻¹) (d) 14ms⁻¹
Correct Answer: […]
The electric vector vibration of an electromagnetic wave is given by E=(50 NC⁻1) sin ω(t-x/c). The intensity of the wave is
Options
(a) 2.3 Wm⁻² (b) 4.3 Wm⁻² (c) 3.3 Wm⁻² (d) 1.8 Wm⁻²
A bar magnet with magnetic moment 2.5×10³ JT⁻¹ is rotating in horizontal plane in the space containing magnetic induction B=4×10⁻⁵ T. The work done in rotating the magnet slowly from a direction parallel to the […]
If μᵥ=1.5230 and μʀ=15.145, then dispersive power of crown glass is
Options
(a) 0.0164 (b) 0.00701 (c) 0.0132 (d) 0.032
Correct Answer:
0.0164
Explanation:
Here μᵥ=1.5230and μʀ=1.5145
Therefore, mean refractive index, μ =(1.523+1.5145) /2 […]
If 20% of a radiactive element decays in 10 days, then amount of original material left after 30 days is (approx)
Options
(a) 78% (b) 62% (c) 51% (d) 48%
Correct Answer:
51%
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