Science unit 2

Question 1

What is a neutral charge

Answer 1

object has equal number of protons and electrons (0)

Question 2

What is a positive charge

Answer 2

objet has more protons than electrons (+)

Question 3

What is a negative charge

Answer 3

object has more electrons than protons (-)

Question 4

What is static electricity

Answer 4

created when objects are rubbed together using friction

Question 5

What is electric force

Answer 5

the force a charged object exerts on a near by object

Question 6

what are the four laws of electric charges

Answer 6

1. like charges REPEL
2. opposite charges ATTRACT
3. charged and neutral objects ATTRAT
4. neutral and neutral objects have NO REACTION

Question 7

What is an electroscope

Answer 7

device that detects the presence of an electric charge

Question 8

What are the two types of electroscope

Answer 8

Pith Ball Electroscope & Metal Leaf Electroscope

Question 9

What is a pith ball electroscope

Answer 9

-to determine if an object has a charge:
-bring object close to neutral pithball
-If object is neutral-pithball won’t move
-If object is charged- pithball will move

Question 10

What is a Metal-Leaf electroscope

Answer 10

-to determine if an object has a charge:
-bring object close to metal ball
-If object is neutral-metal leaf will hang straight down
-If object is charged- metal leafs spread apart
-when you move the object away the leafs will return straight down

Question 11

What are the three methods to charge objects

Answer 11

1. Friction
2. Conduction
3. Induction

Question 12

Rubbing two neutral objects together will result in:

Answer 12

a transfer of electrons. one object will become negatively charged and the other will become positively charged.

Question 13

What is the electroscope series
(trio electric series)

Answer 13

-The electroscope series is a list of materials in order of increasing tendency to gain electrons.
-the higher material will LOSE their electrons and become POSITIVE
-The lower material will GAIN electrons and become negative

Question 14

What are conductors

Answer 14

a substance that allows electrons to pass through them

Question 15

What are insulators

Answer 15

a substance that does not allow electrons to flow freely through them

Question 16

What are the two types of induction

Answer 16

1.temporarily charged buy induction
2.Permanently charged by induction

Question 17

Charging temporarily by induction

Answer 17

(one object charged, one object neutral)
-When a charged object is brought NEAR a neutral object, it INDUCES the electrons to shift
-This results in an uneven distribution of charge, but this will only be temporary because the election will move back to their OG position

Question 18

Charging by induction always results in 2 objects with oposite charges

Answer 18

1. the original object that induces the charge keeps its original charge
2. the other object which was induced receives the opposite charge

Question 19

How to charge by conduction

Answer 19

-Need two objects
-objects must touch
-starting point: at least one (or both) objects must be charged
-End point: Both will end up having the same charge
-How? by moving ELECTRONS(never protons)

Question 20

What is grounding

Answer 20

connecting an object to a big thing (like the earth) to remove an electric charge from an object

Question 21

Lightning

Answer 21

1. Tiny water droplets in clouds move around and they become charged
2. all negatively charged water molecules collect at the bottom of the cloud
3. the negative charges at the bottom of the cloud repel negative charges on the earths surface
4. the ground temporarily becomes induced positively charged. This creates a charged imbalance
5. If the imbalance is big enough, the positive and negative attract, and excess electrons from the cloud will move to the ground
6. this causes the air to be superheated, which causes a flash of light and rumbling sound of thunder