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System of Particles and Rotational Motion
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What is the torque of the force $\overrightarrow {F}=-3 \hat i +\hat j+ 5 \hat k$ acting at a point whose position vector vector is $\overrightarrow {r}= 7 \hat i+3 \hat j +\hat k?$
\[\begin {array} {1 1} (a)\; 14 \hat i- 38 \hat j + 16 \hat k & \quad (b)\;4 \hat i+ 4 \hat j + 6 \hat k \\ (c)\;-14 \hat i+ 38 \hat j - 16 \hat k & \quad (d)\;-21 \hat i+ 3 \hat j + 5 \hat k \end {array}\]
jeemain
physics
class11
unit5
rotational-motion
torques
easy
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asked
Nov 25, 2013
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meena.p
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Jul 10, 2014
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1 Answer
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$\bar {z}=\bar {r} \times \overrightarrow {F}$
So the correct answer is $14 \hat i- 38 \hat j + 16 \hat k$
answered
Nov 25, 2013
by
meena.p
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