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hat(e )(r) is unit Vector along radius o...

`hat(e )_(r)` is unit Vector along radius of a circle shown in figure `hat(e )_(r)` can be represented as `

A

`cos theta hat(i)+sin theta hat(j)`

B

`sin theta hat(i)+cos theta hat(j)`

C

`cos theta hat(i)-sin theta hat(j)`

D

`-cos theta hat(i)+sin theta hat(i)`

Text Solution

Verified by Experts

The correct Answer is:
A
The component of `hat(e )_(r )` along X-axis is
`hat(e )_(r ) cos theta= 1xxcos theta= cos theta`
The component of `hat(e )_(r )` along Y-axis is
`hat(e )_(r ) sin theta= 1xx sin theta= sin theta`
`:. hat(e )_(r )= cos theta hat(i)+sin theta hat(j)`
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A2Z-VECTORS-Chapter Test
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  5. A vector of magnitude 10 N acting in X-Y-plane has componets 8 N and 6...

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  7. A person moves 30 m north, then 30 m, then 20 m towards east and final...

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  8. A particle moves from position 3hat(i)+2hat(j)-6hat(k) to 14hat(i)+13h...

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  9. Normal reaction N is a force exerted by the surface on the block perpe...

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  10. Weight mg of a block is a force acting downward toward centre of the e...

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  11. Three forces are acting on a particle as shown in the figure. To have ...

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  12. Two horizontal forces of magnitudes of 10N and P N act on a particle. ...

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  13. P, Q and R are three coplanar forces acting at a point and are in equi...

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  14. Five forces 2 N, sqrt(3)N, 5 N, sqrt(3) and 2 N respectively act at a ...

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  15. Consider two Vectors vec(F)(1)= 2hat(i)+5hat(k) and vec(F)(2)= 3hat(j)...

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  16. A particle moves with a velocity 6hat(i)-4hat(j)+3hat(k)m//s under the...

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  17. The length of second's hand in watch is 1 cm. The change in Velocity o...

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  18. Asserion: Magnitude of the resultant of two vectors may be less than t...

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  19. Assertion: Multiplying any vector by an scalar is meaningful operatons...

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  20. Assertion: If hat(i) and hat(j) are unit Vectors along x-axis and y-ax...

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