Question

a,b are the magnitudes of vectors a bar and b bar . If a bar × b bar =0 then value of a bar . b bar is

Answer 1

HELLO,

Given that, \(|\vec{a}| =a\) and \(|\vec{b}|=b\) 

Also given that     \(\vec{a}*\vec{b}=0 \)

\(|\vec{a}||\vec{b}|\sin \theta=0\) where \(\theta\) is the angle between \(\vec{a}\) and \(\vec{b}\).

\(\sin \theta =0\)

\(\theta =0\)

We have to find  \(\vec{a}.\vec{b}\)

\(\vec{a}.\vec{b} = |\vec{a}||\vec{b}| \cos \theta\)

\(= ab\cos0\)

\(\vec{a}.\vec{b}=ab\)

I HPE YOU WILL UNDERSTAND.