Question

2 vectors a and b are perpendicular to each other.
what is the value of a.b

Answer 1

Answer:

$\vec{a}.\vec{b} = 0$

Explanation:

Let us consider two vectors $\vec{a} and \vec{b}$.

Their dot product is given by,

$\vec{a}.\vec{b}$ = ab cos α

where a is magnitude of vector a

b is magnitude of vector b

α is the angle between a and b

when $\vec{a} and \vec{b}$ are perpendicular to each other.

α = 90

cos α = cos 90 = 0

so,

$\vec{a}.\vec{b}$ = ab cos α

$\vec{a}.\vec{b}$ = ab (0)

$\vec{a}.\vec{b}$ = 0

Thus, when two vectors are perpendicular to each other their dot product is zero.

$\vec{a}.\vec{b}$ = 0

Answer 2

Answer:0

Explanation:the reason is pretty simple..

a.b or scalar product of a and b = a b cos theta....here as vector a and b are perpendicular to each other, the angle (theta) between them is 90°...

Now cos 90°=0...so a b cos 90°=0....hence a.b = 0.

Hope it helps u