일반물리학 2 — Electric Fields: Problem 50

50 In Fig. 22-44, an electron is shot at an initial speed of \(v_0 = 4.00 \times 10^6 \text{ m/s}\), at angle \(\theta_0 = 40.0^\circ\) from an \(x\) axis. It moves through a uniform electric field \(\vec{E} = (5.00 \text{ N/C})\hat{j}\). A screen for detecting electrons is positioned parallel to the \(y\) axis, at distance \(x = 3.00 \text{ m}\). In unit-vector notation, what is the velocity of the electron when it hits the screen?