Question
Question: A body is rotating with angular velocity \(\overrightarrow{\omega} = \left( 3\widehat{i} - 4\widehat...
A body is rotating with angular velocity ω=(3i−4j+k) The linear velocity of a point having position vector r=(5i−6j+6k) is
A
6i+2j−3k
B
18i+3j−2k
C
−18i−13j+2k
D
6i−2j+8k
Answer
−18i−13j+2k
Explanation
Solution
Here, ω=3i−4j+k
r=5j−−6j+6k
As v=ω×r
\widehat{i} & \widehat{j} & \widehat{k} \\ 3 & - 4 & 1 \\ 5 & - 6 & 6 \end{matrix} \right|$$ =$\widehat{i}( - 24 - ( - 6)) + \widehat{j}(5 - 18) + \widehat{k}( - 18 - ( - 20))$ $$= - 18\widehat{i} - 13\widehat{j} + 2\widehat{k}$$