An electron (charge −1.6 × 10−¹⁹ C)moves on a path perpendicular to the direction of a uniform electric field of strength 2.0 N/C.How much work is done on the electron as it moves 14.0 cm? A)5.6E-19 J B)−2.8E-19 J C)1.6E-19 J D)3.9E-18 J E)zero

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Quizplus · Accepted Answer

When an electron moves perpendicular to the direction of a uniform electric field, the electric field does no work on the electron because the work done by the electric field is given by $W = qEd\cos(\theta)$, where $q$ is the charge, $E$ is the electric field strength, $d$ is the distance moved, and $\theta$ is the angle between the direction of the electric field and the direction of motion. Since $\theta = 90^\circ$ for perpendicular motion, $\cos(90^\circ) = 0$, making $W = 0$.

An Electron (Charge −1