If c is the velocity of light in free space, the time taken by light to travel
If c is the velocity of light in free space, the time taken by light to travel a distance x in a medium refractive index μ is
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(a) x/c (b) μx/c (c) […]
If c is the velocity of light in free space, the time taken by light to travel a distance x in a medium refractive index μ is
Options
(a) x/c (b) μx/c (c) […]
A current of 2 A is made to flow through a coil which has only one turn. The magnetic field produced at the centre is 4πx10⁻⁶ Wb/m². The radius of the coil is
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On heating a ferromagnetic substance above curie temperature
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(a) becomes paramagnetic (b) becomes diamagnetic (c) remains ferromagnetic with constant magnetic susceptibility (d) becomes electromagnetic
Correct Answer:
becomes paramagnetic
Explanation:
No explanation available. […]
For having large magnification power of a compound microscope
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(a) length of the microscope tube must be small (b) focal lengths of objective lens and eye-piece should be large. (c) focal lengths […]
The radius of curvature of the convex face of a plano-convex lens is 12 cm and the refractive index of the material of the lens is 1.5. Then, the focal length of the lens is […]
Two thin lenses of focal lengths f₁ and f₂ are in contact and coaxial. The power of the combination is:
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(a) √ f₁ / f₂ (b) √ f₂ / f₁ (c) f₁ […]
Electrical force is acting between two charges kept in vacuum. A copper plate is placed between the charges, the force now is
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(a) more (b) less but not zero (c) remains unchanged […]
A point charge q is placed at a distance x/2 directly above the centre of a cube of side x. The flux through the cube is
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(a) q/ε₀ (b) q/2ε₀ (c) q/4ε₀ […]
When a p-n junction is reverse biased, then the current through the junction is mainly due to
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(a) Only diffusion of charges (b) Only drift of charges (c) Both drift and diffusion of […]
Maximum kinetic energy of electrons emitted in photoelectric effect increases when
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(a) intensity of light is increased (b) light source is brought nearer the metal (c) frequency of light is decreased (d) […]
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