Theory chapter 3

Dry

Nuisance static charges are more likely to occur when the air is______

semiconductor

Selenium is a(n)______

arrestor

A lightning protection device that is grounded at one end, with the other end close to but not touching the object to be protected, is called a lightning_____

ground to the cloud

If a thundercloud has a positive charge, the current in the lightning bolt will flow from the_______

True

Indicate whether the statement is true or false An electroscope can be used to determine the polarity of an electrostatic charge.

Man-made

In a clothes dryer, the greatest static charges generally are built up on ______fabrics

selenium

The semiconductor material used as a coating on copy machine drums is_____

nuisance

The shock that results from walking across a carpet and touching a doorknob is an example of a(n)______ static charge.

rod

When an object protected by a lightning ______is struck by a lightning bolt, it will bleed the lightning discharge to ground before the protected object can be harmed.

air filter

A precipitator is a type of_______

opposite

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.

insulators

Electrostatic charges occur on______

False

Indicate whether the statement is true or false A thundercloud contains only positive electric charges.

True

Indicate whether the statement is true or false Copy machines operate on the principle of static electricity.

False

Indicate whether the statement is true or false Current always flows from positive to negative.

True

Indicate whether the statement is true or false Lightning is the result of static charges built up in clouds that contain a large amount of moisture.

True

Indicate whether the statement is true or false Lightning rods provide an easy path to ground for current.

False

Indicate whether the statement is true or false Most lightning discharges associated with a cloud occur between the cloud and the ground.

electrons

Insulators are the only materials that can hold ________stationary.

Arrestor

Power lines are often protected by lightning _______that exhibit a very high resistance at the normal voltage of the line.

are not

Static electricity refers to electrons that _____moving.

negative

The precipitator uses a high-voltage DC power supply to provide a set of wies with a positive charge and a set of plates with a ____ charge

useful

The static charge sometimes used during spray painting is an example of a(n) ______static charge

from negative to positive

Within a lightning bolt, current flows ______