The change in the kinetic energy of the calcium ion's is 6.4 x 10⁻¹⁶ J.
The change in the kinetic energy of the ion's which accelerated through the given potential difference is calculated as follows;
ΔK.E = qV
where;
Substitute the given parameters in the above equation and solve for change in kinetic energy.
ΔK.E = (2e)V
ΔK.E = (2 x 1.6 x 10⁻¹⁹) x (2.0 x 10³)
ΔK.E = 6.4 x 10⁻¹⁶ J
Thus, the change in the kinetic energy of the calcium ion's is 6.4 x 10⁻¹⁶ J.
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