Grade 9 Electricity (static)

Question 1

Electricity

Answer 1

A form of energy that results from the interaction of charged particles, such as electrons or protons

Question 2

Static charge

Answer 2

An electric charge that tends to stay on an object rather than flowing away

Question 3

Charging by friction

Answer 3

A process in which objects made from different materials rub against rub against eachother, producing a net static charge on each

Question 4

Electrostatic series

Answer 4

A list of materials that have been arranged according to their ability to hold on to electrons

Question 5

Insulator

Answer 5

A material in which electrons cannot move from one atom to another

Question 6

Conductor

Answer 6

A material in which electrons can move easily between atoms

Question 7

Semiconductor

Answer 7

A material in which electrons can move fairly well between atoms

Question 8

Ground

Answer 8

An object that can supply a very large number of electrons to, or can remove a very large number of electrons from, a charged object, thus neutralizing the object

Question 9

Types of charge

Answer 9

• Negative (the substance has gained electrons)
• Positive (the substance has lost electrons)
• neutral (any object that has no overall charge)

Question 10

The law of attraction and repulsion

Answer 10

1. Opposite charges attract
2. Alike charges repel
3. Neutral objects are attracted to charged objects

Question 11

Static will not occur without…

Answer 11

An insulator

Question 12

_____ cannot hole static charge

Answer 12

Conductors

Question 13

Example of a ground

Answer 13

A lightning rod

Question 14

Charging by contact

Answer 14

When a charged object makes contact with a neutral object, electrons are transferred. The neutral object will get the same charge as the charging object

Question 15

Charging by induction using a negatively charged rod (4)

Answer 15

• the electroscope is neutral
• when a negatively charged rod is brought near the sphere electrons are repelled out through the ground
• the ground is removed with the (-) charged rod still near
• rod is removed, since the electroscope lost electrons it is now (+) charged

Question 16

Charging by induction using a positively charged rod (4)

Answer 16

• the electroscope is neutral
• when a positively charged rod is brought near the sphere electrons come from the ground to the electroscope to balance the (+) charges in the rod
• equal (+) and (-) when you include the charges in the rod
• rod is removed, since the electroscope obtained electrons it is now (-) charged

Question 17

Charging by induction

Answer 17

When a charged object is brought near but not touching a neutral object and then is grounded. Electrons will ne transferred to or from the ground resulting in the neutral object gaining the opposite charge as the charging object

Question 18

induced charge separation

Answer 18

When a charged object is placed near another object, electrons will shift positions. Electrons will be repelled by a negative object, or attracted to a positive charge. This will produce an objects with two regions of opposite charge.

Question 19

Electrostatic series

Answer 19

To know what items will gain/lose electrons when rubbed together, we use an electrostatic series. Materials that have a tendency to gain electrons are more likely to become negatively charged.