Iluminance of `2.4 xx 10^(5)lm//m^(2)` of the surface is produced by sunlight falling normally on the surface of the earth. The distance of the earth the sun is `1.5 xx 10^(8)km`. Calculate the luminous intensity and luminous flux of the sun.
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Photosysthesis si a bio process by which plants make energy rich molecules from low energy molecules with the help of energy from sunlight . The photo
Correct Answer - Energy of 1 mole of photon = `nxx (hC)/(lambda) = 6.023 xx 10^(23) xx (6.625 xx 10^(-34) xx 3 xx 10^(8))/(650 xx 10^(-9) xx 10^(3)) = 184...
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Earth receives 1400 `W//m^(2)` of solar power. If all the solar energy falling on a lens of area `0.2m^(2)` is focussed onto a block of ice of mass 2.
Heat received per second `=(1400)(0.2)=280J` Required heat for meting of the block=(0.28) `(3.3xx10^(5))=9.24xx10^(4)J` Required time `(9.24xx10^(4))/(280xx60)=5.5` minutes.
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If a ray is incident normally to the surface of a concave mirror, through which point will it pass after reflection?
Option : B. From Centre of Curvature
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A thin film having refractive index` mu" = 1.5"` has air on both sides. It is illuminated by white light falling normally on it. Analysis of the refle
Correct Answer - (a)900 nm (b)415nm ,491nm,600nm,771nm
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Intensity of sunlight on the surface of the earth is `I = 1400 W//m^(2)` (neglecting atmospheric absorption). (a) Find the Wattage of the Sun. (b) Ass
Correct Answer - (a) `3.96 xx 10^(26) W` , (b) `1.19 xx 10^(45)` (c) `4.4 xx 10^(9) kg//s`.
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Which of the following is not normally produced by the body ?
Correct answer is (B) Vitamin
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A point source emitting alpha particles is placed at a distance of 1 m from a counter which records any alpha particle falling on its `1 cm^2`window.
Correct Answer - `[1.05 xx 10^(-7) secc^(-1)]`
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Find the distance of a heavenly object from the earth if the parallactic angle as measured from two places at a distance of `6.284xx10^(6)m` apart is
Correct Answer - `1.8xx10^(8)m`
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20. A coconut of mass \( 2 Kg \) is falling from a coconut free of height \( 10 m \). Find the potential energy, kinetic energy and total energy at the following points. \( \left( g =10 m / s ^{2}\right) \) a) Before falling from the coconut tree. b) Just before hilting the ground. c) At a height \( 4 m \) from the ground. d) Which law is evident from this example?
(a) Given m = 2 kg h = 10 m Potential energy at before falling from the coconut tree. u = mgh u = 2 x 10 x 10 u = 200 joule Kinetic energy will...
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If R is the radius of the Earth and g is the acceleration due to gravity on the Earth’s surface, the mean density of the Earth is
Correct option is: (D) \(\frac{3g}{4\pi RG}\)
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