Question:
Let ab , and ()ab × be unit vectors. What is (. )ab equal to?
Let ab , and ()ab × be unit vectors. What is (. )ab equal to?
Options:
- a) 0
- b) 1 2
- c) 1
- d) 3
- a) 0
- b) 1 2
- c) 1
- d) 3
correct answer : a)
Explanation:
\ | a
| = | b
| = | ab
× | = 1
sinq = ||
|| ||
ab
ab
×
= 1.
\ q = 2
π
Now, ab
. = | a
|| b
| cos 2
π = 0
\ | a
| = | b
| = | ab
× | = 1
sinq = ||
|| ||
ab
ab
×
= 1.
\ q = 2
π
Now, ab
. = | a
|| b
| cos 2
π = 0