This preview shows page 1. Sign up to view the full content.
Unformatted text preview: x/ 2 in the denominator and write tan θ ≈ x/ 2 L . This is equivalent to approximating tan θ by sin θ . The magnitude of the electrical force of one ball on the other is F e = q 2 4 πε x 2 by Eq. 224. When these two expressions are used in the equation mg tan θ = F e , we obtain mgx 2 L ≈ 1 4 πε q 2 x 2 = ⇒ x ≈ µ q 2 L 2 πε mg ¶ 1 / 3 . (b) We solve x 3 = 2 kq 2 L/mg ) for the charge (using Eq. 225): q = r mgx 3 2 kL = s (0 . 010 kg)(9 . 8 m / s 2 )(0 . 050 m) 3 2(8 . 99 × 10 9 N · m 2 / C 2 )(1 . 20 m) = ± 2 . 4 × 10 − 8 C ....
View
Full
Document
This note was uploaded on 11/12/2011 for the course PHYS 2001 taught by Professor Sprunger during the Fall '08 term at LSU.
 Fall '08
 SPRUNGER
 Physics, Force, Gravity

Click to edit the document details