# The flight to the center of the disc

A particle $$P$$ having a charge of $$-1\ \mu\text{C}$$ and mass 2 g is held at a distance of $$x=1\text{ m}$$ from the center of a disc, as shown in the figure above. The disc has a radius of 2 m and surface charge density $$6.84\times 10^{-4} \text{ C/m}^2$$.

The particle is released, and flies toward the disc. Find the velocity (in m/s) of the particle when it has covered half the distance.

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