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If a unit vector represented by 0.5hati-...

If a unit vector represented by `0.5hati-0.8hatj+chatk`, then the value of 'c' is :

A

`1`

B

`sqrt(0.11)`

C

`sqrt(0.01)`

D

`sqrt(0.39)`

Text Solution

Verified by Experts

The correct Answer is:
B
`sqrt((0.5)^(2)+(-0.8)^(2)+c^(2))=1`
`rArr 0.25+0.64+c^(2)=1`
`rArr c^(2)=0.11 rArr c= +- sqrt(0.11)`
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ALLEN -MISCELLANEOUS-Exercise-01
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