Question

If two non-zero vectors a and b are parallel to each other . Then a.b is=

(a) scalar quantity
(b) vector quantity
(c) |a| |b|
(d) |a| |b| n cap.....where n cap is a unit vector

pls help​

Answer 1

Answer:

the two non zero vectors are lal lbl

Answer 2

If two non-zero vectors a and b are parallel to each other. Then a.b is      |a| |b| (Option c).

Given,

a and b are non zero vectors.

Vector a and b are parallel to each other.

To Find:

The value of a.b

Solution:

The dot product of vector a and vector b is,

a.b= |a| |b| cos∅ [ Here ∅ is angle between two vector a and b]

⇒a.b= |a| |b| cos0° [ Both vectors are parallel to each other so angle between them is 0°]

⇒a.b= |a| |b| (1)  [cos0°= 1]

⇒a.b = |a| |b|

Hence, If two non-zero vectors a and b are parallel to each other . Then a.b is |a| |b|.