यदि `0.5hati+0.8hatj+ chatk` एकांक सदिश है, तब C का मान है

Options

A. 1
B. `sqrt(0.11)`
C. `sqrt(0.01)`
D. `0.39`

Answer

B

Explanation

`vecr=0.5hatj+0.8hatj+chatk`
`|vecr|=1= sqrt((0.5)^(2)+(0.8)^(2)+c^(2))`
`0.25+0.64+c^(2)=1`
`C^(2)=0.11 rArr C= sqrt(0.11)`