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JEE PHYSICS MCQ: MOTION IN PLANE

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Statement-I: If

\vec{a}

is perpendicular to

\vec{b}

and

\overrightarrow{{c}}

, then

\overrightarrow{{a}} \times(\overrightarrow{{b}} \times \overrightarrow{{c}})=0

Statement-II: If

\overrightarrow{{b}}

is perpendicular to

\overrightarrow{{c}}

, then

\overrightarrow{{b}} \times \overrightarrow{{c}}=0

View answer and explanation

Correct option: B

Statement-I is true and statement-II is false

Option B is correct because if

\vec{a}

is perpendicular to both

\vec{b}

and

\vec{c}

, then

\vec{b} \times \vec{c}

will not be zero, and

\vec{a} \times (\vec{b} \times \vec{c})

will be non-zero, and

\vec{b}

being perpendicular to

\vec{c}

does not mean their cross product is zero.

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0^{\circ}

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\theta

and another ball is thrown at an angle

\left(90^{\circ}-\theta\right)

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