quiz_solutions01

# Fundamentals of Physics, (Chapters 21- 44) (Volume 2)

This preview shows page 1. Sign up to view the full content.

PY212 Solutions Quiz 1 (a) For the net force to be in the + x direction, the y components of the individual forces must cancel. The angle of the force exerted by the q 1 = 50 μ C charge on q 3 = 30 μ C is , 7 . 33 cm 0 . 3 cm 0 . 2 tan o 1 1 = = θ and the angle of force exerted on q 3 by Q is at . 6 . 26 cm 0 . 4 cm 0 . 2 tan o 1 = = Q The magnitudes of the forces are ( ) ( ) 2 2 2 3 23 2 2 2 3 1 13 ) m 020 . 0 ( ) m 040 . 0 ( , ) m 020 . 0 ( ) m 030 . 0 ( + = + = q Q k F q q k F y Cancellation of y components requires ( ) ( ) o 2 2 2 3 o 2 2 2 3 1 6 . 26 sin ) m 020 . 0 ( ) m 040 . 0 ( 7 . 33 sin ) m 020 . 0 ( ) m 030 . 0 ( + = + q Q k q q k
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: from which we obtain | Q | = 95 μ C. Charge Q is “pulling” on q 3 , so (since q 3 &gt; 0) we conclude Q = –95 μ C. (b) We now require that the x components cancel and therefore, ( ) ( ) o 2 2 2 3 o 2 2 2 3 1 6 . 26 cos ) m 020 . ( ) m 040 . ( 7 . 33 cos ) m 020 . ( ) m 030 . ( + = + q Q k q q k from which we obtain Q = 72 μ C....
View Full Document

## This document was uploaded on 07/10/2009.

Ask a homework question - tutors are online