PHYSICS · Multi-part · AP · Physics 2: Algebra-based · Electric Force Field and Potential · Electric Force Field and Potential
Problem
Three ions—C, D, and E—are accelerated individually from rest through an identical electric potential difference of 320 V inside a mass spectrometer. Their physical properties are given in the table.
Ion Charge Mass
C +e9.11×10−31kg
D +2e6.64×10−26kg
E −e9.11×10−31kg
Assume the ions do not interact with one another and are affected only by the electric field during the acceleration stage.
(a) For each ion, calculate the work done by the electric field during the acceleration. Present your answers to three significant figures.
(b) Using your results from part (a), determine the kinetic energy of each ion after acceleration.
(c) Compute the speed of each ion after acceleration. Rank the ions from fastest to slowest speed and justify any equalities you find.
(d) Despite having identical masses, ions C and E move in opposite directions once released. Explain why the magnitudes of their speeds are the same or different, referencing your calculations and underlying physical principles.