1. Electrostatic Electricity, Electric Charge (CH 15
Homework No. 1 (Electrostatics)
Due date: October 4 or 5 October Name: _____________________
If you rub a glass rod with a silk cloth: a) what charge polarity will the glass rod acquire?); (b) What method of charge transfer is being used? __________________________________________________
If you charge a glass rod and balloon each with a silk cloth, will the rod and balloon attract or repel each other? ______________________________________________________________________________
No. 23 In calculating planetary orbits around the sun, why can astronomers safely ignore the electric force? ______________________________________________________________________________
No. 26 Coulomb’s Law is also called an inverse square law. What does it tell you about the relationship between force and distance? ____________________________________________________________
An electron and a proton are separated by 2.0 nm. Using the Coulomb’s Law we can calculate the magnitude of the force on the electron, F = k(q1 x q2)/r2.= 5.8x N; What is the net force on the system? _____________________________________________________________________________
The electric field due to negative charge (a) varies as 1/r; (b) points toward the charge, (c ) points away from the charge or (d) has a finite charge. __________________________________________________
Could the electric field due to two charges ever be zero at some location nearby? If yes,describe and sketch the situation. ____________________________________________________________________

2. Electrostatic Electricity, Electric Charge (CH 15) (with answers)
Homework No. 1 (Electrostatics)
Due date: October 4 or 5 October Name: _____________________
If you rub a glass rod with a silk cloth: a) what charge polarity will the glass rod acquire? A: Glass is positive); b) What method of charge transfer is being used? A: By contact
If you charge a glass rod and balloon each with a silk cloth, will the rod and balloon attract or repel each other? A: attract
No. 23 In calculating planetary orbits around the sun, why can astronomers safely ignore the electric force? A: 23c Objects are electrically neutral.
No. 26 Coulomb’s Law is also called an inverse square law. What does it tell you about the relationship between force and distance? A.: Force depends on inverse square of the distance between the charges.
An electron and a proton are separated by 2.0 nm. Using the Coulomb’s Law we can calculate the magnitude of the force on the electron, F = k(q1 x q2)/r2.= 5.8x N; What is the net force on the system? A: zero because the two forces add up to zero.
6) The electric field due to negative charge (a) varies as 1/r; (b) points toward the charge, (c ) points away from the charge or (d) has a finite charge. A: b
Could the electric field due to two charges ever be zero at some location nearby? If yes, describe and sketch the situation. A: 49 Yes! When the electric fields are equal in magnitude and opposite in direction at a location. q2
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