{[ promptMessage ]}

Bookmark it

{[ promptMessage ]}

Assigment 3

# Assigment 3 - ASSIGNMENT 3 21.4.IDENTIFY:Use the mass m of...

This preview shows pages 1–2. Sign up to view the full content.

ASSIGNMENT 3 21.4.I DENTIFY : Use the mass m of the ring and the atomic mass M of gold to calculate the number of gold atoms. Each atom has 79 protons and an equal number of electrons. S ET U P : 23 A 6.02 10 atoms/mol N = . A proton has charge + e . E XECUTE : The mass of gold is 17.7 g and the atomic weight of gold is 197 g mol. So the number of atoms is 23 22 A 17.7 g (6.02 10 atoms/mol) 5.41 10 atoms 197 g mol N n = = . The number of protons is 22 24 p (79 protons/atom)(5.41 10 atoms) 4.27 10 protons n = = . 19 5 p ( )(1.60 10 C/proton) 6.83 10 C Q n - = = . (b) The number of electrons is 24 e p 4.27 10 . n n = = E VALUATE : The total amount of positive charge in the ring is very large, but there is an equal amount of negative charge. 21.26. I DENTIFY : For a point charge, 2 q E k r = . S ET U P : E r is toward a negative charge and away from a positive charge. E XECUTE : (a) The field is toward the negative charge so is downward. 9 9 2 2 2 3.00 10 C (8.99 10 N m /C ) 432 N/C (0.250 m) E - = = . (b) 9 2 2 9 (8.99 10 N m /C )(3.00 10 C) 1.50 m 12.0 N/C k q r E - ״� = = = E VALUATE :

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}