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The torque of force barF= (2 hat i -3 ha...

The torque of force `barF= (2 hat i -3 hat j + 4 hat k)` newton acting at the point =` (3 hat i + 2 hat j+ 3 hat k)` metre about origin is `tau` (in N-m). Find x. component of `tau` .

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To find the x-component of the torque \(\tau\) produced by the force \(\bar{F} = (2 \hat{i} - 3 \hat{j} + 4 \hat{k})\) acting at the point \(\bar{R} = (3 \hat{i} + 2 \hat{j} + 3 \hat{k})\) about the origin, we can follow these steps: ### Step-by-Step Solution: 1. **Identify the vectors**: - Force vector: \(\bar{F} = 2 \hat{i} - 3 \hat{j} + 4 \hat{k}\) - Position vector: \(\bar{R} = 3 \hat{i} + 2 \hat{j} + 3 \hat{k}\) 2. **Use the torque formula**: - The torque \(\tau\) is given by the cross product of the position vector \(\bar{R}\) and the force vector \(\bar{F}\): \[ \tau = \bar{R} \times \bar{F} \] 3. **Set up the determinant for the cross product**: - We can express the cross product using the determinant of a matrix: \[ \tau = \begin{vmatrix} \hat{i} & \hat{j} & \hat{k} \\ 3 & 2 & 3 \\ 2 & -3 & 4 \end{vmatrix} \] 4. **Calculate the determinant**: - Expanding the determinant: \[ \tau = \hat{i} \begin{vmatrix} 2 & 3 \\ -3 & 4 \end{vmatrix} - \hat{j} \begin{vmatrix} 3 & 3 \\ 2 & 4 \end{vmatrix} + \hat{k} \begin{vmatrix} 3 & 2 \\ 2 & -3 \end{vmatrix} \] 5. **Calculate each of the 2x2 determinants**: - For \(\hat{i}\): \[ \begin{vmatrix} 2 & 3 \\ -3 & 4 \end{vmatrix} = (2)(4) - (3)(-3) = 8 + 9 = 17 \] - For \(-\hat{j}\): \[ \begin{vmatrix} 3 & 3 \\ 2 & 4 \end{vmatrix} = (3)(4) - (3)(2) = 12 - 6 = 6 \] - For \(\hat{k}\): \[ \begin{vmatrix} 3 & 2 \\ 2 & -3 \end{vmatrix} = (3)(-3) - (2)(2) = -9 - 4 = -13 \] 6. **Combine the results**: - Thus, the torque vector \(\tau\) is: \[ \tau = 17 \hat{i} - 6 \hat{j} - 13 \hat{k} \] 7. **Extract the x-component**: - The x-component of \(\tau\) is simply the coefficient of \(\hat{i}\): \[ \text{x-component of } \tau = 17 \] ### Final Answer: The x-component of the torque \(\tau\) is \(17 \, \text{N-m}\).
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