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If a→ is a nonzero vector of magnitude 'a' and λ a nonzero scalar, then λa→ is unit vector if ______. - Mathematics

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Question

If `veca` is a nonzero vector of magnitude 'a' and λ a nonzero scalar, then λ`veca` is unit vector if ______.

Options

  • λ = 1

  • λ = -1

  • a = |λ|

  • `a = 1/|λ|`

MCQ
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Solution

If `veca` is a nonzero vector of magnitude ‘a’ and λ a nonzero scalar, then λ`veca` is unit vector if `underline(a = 1/|λ|)`

Explanation:

Given : Resultant of `veca` = a

That is, `|veca| = a`

`λveca` is a unit vector

`|lambdaveca| = 1`

`|lambda||veca| = 1`

`|lambda|a = 1``

`a = 1/|lambda|`

Hence, option `a = 1/|lambda|` is correct.

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Magnitude and Direction of a Vector
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Chapter 10: Vector Algebra - Exercise 10.3 [Page 448]

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NCERT Mathematics Part 1 and 2 [English] Class 12
Chapter 10 Vector Algebra
Exercise 10.3 | Q 18 | Page 448

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