Chapter 3
A thundercloud cannot contain both positive and negative electric charges
False
Current always flows from positive to negative
False
An electroscope can be used to determine the polarity of an electrostatic charge
True
Lightning is the result of static charges built up in clouds that contain a large amount of moisture
True
Lightning rods provide an easy path to ground for current
True
The application of static electricity is used during the manufacture of sandpaper
True
The discharge of static electricity in thunderclouds creates lightning bolts
True
A precipitator is a type of
air filter
The lightning protection device that does not connect directly to the object to be protected is called the lightning ______________
arrestor
Insulators are the only materials that can hold ____________ stationary
electrons
The current flow that occurs within a lightning bolt flows
from negative to positive
If a thundercloud has a positive charge, the current in the lightning bolt will from from the
ground to cloud
Electrostatic charges occur on _____________
insulators
A static electric charge is an electric charge which ____________ moving
is not
The precipitator uses a high-voltage DC power supply to provide a set of wires with a positive charge and a set of plates with a ___________ charge
negative
If you walk across a carpet, touch the doorknob and get a shock, the shock was a result of a(n) ____________ static charge
nuisance
The static charge that accumulates on clothes in the dryer is a(n) ___________ charge
nuisance
Bringing a charged test object near the ball of a charged electroscope causes the leaves to move closer together. This indicates that the test object charge is the ____________ polarity as the electroscope charge
opposite
When an object protected by a lightning ____________ is struck by a lightning, it will bleed the lightning discharge to ground before the protected object can be harmed
rod
The semiconductor material used a a coating on copy machine drums is _______________
selenium
Selenium is a(n) ____________
semiconductor
The static charge sometimes used during spray painting is called a(n) _____________ static charge
useful