A particle of mass m is projected with speed u at an angle `theta` with the horizontal. Find the torque of the weight of the particle about the point of projection when the particle is at the highest point.

Explanation

To find the torque of the weight of a particle about the point of projection when the particle is at its highest point, we can follow these steps:

### Step 1: Understand the problem
We have a particle of mass \( m \) projected with an initial speed \( u \) at an angle \( \theta \) with the horizontal. We need to find the torque due to the weight of the particle when it reaches its highest point.

### Step 2: Identify the forces acting on the particle
At the highest point of its trajectory, the only force acting on the particle is its weight, which is given by:
\[
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