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JEE · NEET Previous Year Question

$If F is the force acting on a particle having position vector y and τ be the torque of this force about the origin, then$

Topic: NEET PYQ

Answer: B. Full step-by-step solution below.

A $r \cdot τ > 0 and F \cdot τ < 0$
B $r \cdot τ = 0 and F \cdot τ = 0$
C $r \cdot r = 0 and F \cdot r \neq = 0$
D $r \cdot τ \neq = 0 and F \cdot τ = 0$

Correct answer: B

Solution

(b) : Torque is always perpendicular to F as well as r . r \cdot τ = 0 as well as F \cdot τ = 0.

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