You sometimes create a spark when you touch a doorknob after shuffling your feet on a carpet.
Question:
a. The average distance between ionizing collisions is 2.0 μm.
(The electron€™s mean free path is less than this, but most collisions are elastic collisions in which the electron bounces with no loss of energy.) What acceleration must an electron have to gain 2.0 × 10-18 J of kinetic energy in this distance?
b. What force must act on an electron to give it the acceleration found in part a?
c. What strength electric field will exert this much force on an electron? This is the breakdown field strength. The measured breakdown field strength is a little less than your calculated value because our model of the process is a bit too simple. Even so, your calculated value is close.
d. Suppose a free electron in air is 1.0 cm away from a point charge.
What minimum charge is needed to cause a breakdown and create a spark as the electron moves toward the point charge?
Step by Step Answer:
Physics for Scientists and Engineers A Strategic Approach with Modern Physics
ISBN: 978-0133942651
4th edition
Authors: Randall D. Knight