Question #42309

This question tests the student's ability to handle angular momentum for a particle subjected to a time-varying, non-central force.

The primary trap is the assumption of constant torque or using the final torque value multiplied by time ($\vec{\tau}_{final} \times t$), which incorrectly simplifies the dynamic angular impulse integral $\int \vec{\tau}(t) dt$.

Furthermore, by asking for the angular momentum about a shifted reference point $P(0,1)$ rather than the origin, it penalizes students who blindly apply $\vec{r} \times \vec{v}$ without adjusting the position vector to the correct reference frame.

The dual-path solution (kinematics vs. torque integration) ensures that students who rely on static formulas will fail, forcing a fundamental application of Newton's Second Law and the definition of angular momentum.