Electric Force on an Electron Because electrons are extremely small and often escape atoms to move freely, they are usually treated as the idealization of a point-charge. Problems typically involve an electron placed in a uniform electric field and allowed to accelerate. The electrical charge of the electron is considered the fundamental value of charge encountered in the universe. Its value is –1.602 × 10-19 C, but I will usually round it and write it –16 × 10-20 just to make it easier to work with. Every other object’s charge must exist as a multiple of this tiny number, though it can be positive since the proton, usually locked away in the atomic nucleus, has the same value with the opposite sign. Suppose that an electron (e-) is released from rest in a uniform 1 µ C electric field oriented in the x-direction—that is, E = 1 × 10 − 6 ˆ x N / C . (See the figure to the right.) What will the electron’s velocity be after eighteen seconds? This will require recalling some equations from a previous
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This note was uploaded on 04/05/2012 for the course PHYS 131 taught by Professor Tibbets during the Spring '11 term at Cuyamaca College.