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Find the magnitude of two vectors anda→andb→, having the same magnitude and such that the angle between them is 60° and their scalar product is 12. - Mathematics

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प्रश्न

Find the magnitude of two vectors `veca and vecb`, having the same magnitude and such that the angle between them is 60° and their scalar product is `1/2`.

योग

उत्तर

We have, `theta = 60^circ, veca xx vecb = 1/2, |veca| = |vecb|`

If the angle between vectors `veca, vecb` is θ, then

Now, `costheta = (veca xx vecb)/(|veca||vecb|)`

`cos 60^circ = (1/2)/|veca|^2; 1/2 = 1/(2|veca|^2)`

`|veca|^2 = 1; |veca| = 1`

`|veca| = 1, |vecb| = 1`

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Magnitude and Direction of a Vector
  क्या इस प्रश्न या उत्तर में कोई त्रुटि है?
अध्याय 10: Vector Algebra - Exercise 10.3 [पृष्ठ ४४८]

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एनसीईआरटी Mathematics [English] Class 12
अध्याय 10 Vector Algebra
Exercise 10.3 | Q 8 | पृष्ठ ४४८

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