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Question
Find the direction cosines and direction ratios for the following vector
`hat"j"`
Solution
`hat"j" = 0hat"i" + hat"j" + 0hat"k"`
The direction ratios of the vector `hat"j"` are (0, 1, 0)
The direction cosines of the vector `hat"j"` are
`0/sqrt(0^2 + 1^2 + 0^2), 1/sqrt(0^2 + 1^2 + 0^2), 0/sqrt(0^2 + 1^2 + 0^2)`
`0/1, 1/1, 0/1`
(0, 1, 0)
Direction ratios = (0, 1, 0)
Direction cosines = (0, 1, 0)
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