$$\overrightarrow a = 3\hat i - 5\hat j$$ and $$\overrightarrow b = 6\hat i + 3\hat j$$ are two vectors and $$\overrightarrow c $$ is a vector such that $$\overrightarrow c = \overrightarrow a \times \overrightarrow b $$ then $$\left| {\overrightarrow a } \right|:\left| {\overrightarrow b } \right|:\left| {\overrightarrow c } \right|$$
A.
$$\sqrt {34} :\sqrt {45} :\sqrt {39} $$
B.
$$\sqrt {34} :\sqrt {45} :39$$
C.
$$34:39:45$$
D.
$$39:35:34$$
Answer :
$$\sqrt {34} :\sqrt {45} :39$$
Solution :
We have $$\overrightarrow a \times \overrightarrow b = 39\overrightarrow k = \overrightarrow c $$
Also $$\left| {\overrightarrow a } \right| = \sqrt {34} ,\left| {\overrightarrow b } \right| = \sqrt {45} ,\left| {\overrightarrow c } \right| = 39;$$
$$\therefore \left| {\overrightarrow a } \right|:\left| {\overrightarrow b } \right|:\left| {\overrightarrow c } \right| = \sqrt {34} :\sqrt {45} :39.$$
Releted MCQ Question on Basic Physics >> Kinematics
Releted Question 1
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