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Which of the following are correct expression for torque acting on a body? A. \(\vec{\tau}=\vec{r}\times\vec{L}\) B. \(\vec{\tau}=\dfrac{d}{dt}(\vec{r}\times\vec{p})\) C. \(\vec{\tau}=\vec{r}\times\dfrac{d\vec{p}}{dt}\) D. \(\vec{\tau}=I\vec{\alpha}\) E. \(\vec{\tau}=\vec{r}\times\vec{F}\) (\(\vec{r}\) = position vector; \(\vec{p}\) = linear momentum; \(\vec{L}\) = angular momentum; \(\vec{\alpha}\) = angular acceleration; \(I\) = moment of inertia; \(\vec{F}\) = force; \(t\) = time) Choose the correct answer from the options given below:
- (1) B, D and E Only
- (2) A, B, D and E Only
- (3) B, C, D and E Only
- (4) C and D Only
Correct answer: (3) B, C, D and E Only
Solution
Options B, C, D, and E correctly express torque in different contexts: B relates torque to the rate of change of angular momentum, C connects torque to the change in linear momentum, D defines torque in terms of moment of inertia and angular acceleration, and E describes torque as the cross product of the position vector and force.
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