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A vecA=2hati+4hatj-5hatk the direction o...

A `vecA=2hati+4hatj-5hatk` the direction of cosines of vector `vecA` are

A

`2/(sqrt(145)),4/(sqrt(45))` and `(-5)/(sqrt(45))`

B

`1/(sqrt(45)),2/(sqrt(45))` and `3/(sqrt(45))`

C

`4/(sqrt(45)), 0` and `4/(sqrt(45))`

D

`2/(sqrt(45)), 2/(sqrt(45))` and `5/(sqrt(45))`

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A
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ERRORLESS -VECTORS-Exercise
  1. If vecA=3hati+4hatj and vecB=7hati+24hatj, find a vector having the sa...

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  2. Vector vec(A) makes equal angles with x-,y-,and z-axis. Find the value...

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  3. A vecA=2hati+4hatj-5hatk the direction of cosines of vector vecA are

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  4. The vector that must be added to the vector hati-3hatj+2hatk and 3hati...

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  5. How many minimum number of coplanar vector having different magnitudes...

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  6. A hall has the dimensions 10 m xx 12 m xx 14 m. A fly starting at one ...

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  7. 100 coplanar forces each equal to 10 N act on a body. Each force makes...

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  8. The magnitude of a given vector with end points(4, -4,0) and (-2, -2,0...

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  9. The expression (1/(sqrt(2))hat(i)+1/(sqrt(2))hat(j)) is a

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  10. The angle made by the vector vecA=2hati+3hatj with Y-axis is

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  11. The unit vector along hati+hatj is

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  12. A vector is represented by 3hati+2hatj+2hatk. Its length in XY plane i...

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  13. Five equal forces of 10 N each are applied at one point and all are ly...

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  14. Set the angles made by following vectors with x-axis in the increasing...

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  15. Any vector in an arbitrary direction can always be replaced by two (or...

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  16. Angular moment is

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  17. Which of the following is a vector

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  18. If vecP= vecQ then which of the following is NOT correct?

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  19. The positoin vector of a particle is vecr=(acos omegat)hati+(asinomega...

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  20. Which of the following is a scalar quantity

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