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Solid angle subtended by hemisphere at c...

Solid angle subtended by hemisphere at centre is ...... .

A

1sr

B

`2pi sr`

C

`4pi sr`

D

`pi sr`

Text Solution

Verified by Experts

Surface area of sphere of radius `r=4pi r^(2)`
`:.` Surface are of hemisphere `DeltaA=2pi r^(2)`
`:.` Solid angle `=(DeltaA)/(r^(2))=(2pir^(2))/(r^(2))=2pi sr`
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KUMAR PRAKASHAN-UNITS AND MEASUREMENT-SECTION -E (MULTIPLE CHOICE QUESTIONS (MCQS) (MCQS ASKED IN GUJARAT BOARD AND COMPETITIVE EXAMS)
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  4. If error in measurement of a length of a cube is 3%, what is error in ...

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  8. If the formula for a physical quantity is W=(a^(4)b^(3))/(c^(2)sqrt(d)...

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  9. 1 MKS unit of power = ....... CGS unit of power.

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  10. In the equation b=a^(2) cos^(2)((2pi beta gamma)/(alpha)). If the unit...

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  11. When a current of (5 +- 0.5)A flows through a wire, it develops a pote...

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  12. 1 fm=... nm

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  13. The dimensional formula of energy propagated per unit area at a given ...

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  14. Numbers of significant figures in 4.033 and 0.004033 are ...... respec...

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  15. If frequency (F), velocity (v) and density (D) are considered as funda...

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  16. Dimensional formula of thermal resistance R(H).....

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  17. In (P+(a)/(V^(2)))(V-b)=RT equation the, a,b will be ..... Where P= Pr...

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  18. 1g=.... Amu

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  19. If Z=A^(4) then relatie error in Z is .....

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  20. ..... is the dimensional formula fo Gravitational potential energy.

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