Two vectors have magnitudes 3 and 5 . If angle between them is 60^o , then dot product of two vector

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3-1.Vectors

easy

The two vectors have magnitudes $3$ and $5$. If angle between them is $60^o$, then the dot product of two vectors will be

A

$7.5$

B

$6.5$

C

$8.4$

D

$7.9$

Solution

$\vec A.\vec B = AB\,\cos \,\theta = 3 \times 5 \times \cos \,{60^o} = 7.5$

Standard 11

Physics

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