If ` -> a` is a nonzero vector of magnitude a and `lambda` a nonzero scalar, then `lambda` ` -> a` is unit vector if (A) `lambda =" "1` (B) `lambda=" "" "1` (C) `a" "=" "|lambda|` (D) `a" "=" "1/(|lambda|)`

Options

A. `lambda=pm1`
B. `a=|lambda|`
C. `a=(1)/(|lambda|)`
D. `a=(1)/(lambda)`only

Answer

C

Explanation

As given, `lambda vec(a)` is a unit vector.
`rArr |lambda vec(a)|=1`
`rArr |lambda||vec(a)|=1`
`rArr a=(1)/(|lambda|) [:' |vec(a)|=a]`