Topic 1: Electrical Charges

Question 1

Charged

Answer 1

• Materials that attract or repel each other
• Charges are produced when objects are touched, rubbed or moved close together and than separated
  Ex. touching a door after walking on carpet

Question 2

Proton

Answer 2

• Positively charged particle
• Less electrons than protons

Question 3

Electron

Answer 3

• Negatively charged particle
• More electrons than protons

Question 4

Student Observation

Answer 4

1. Uncharged acetate + uncharged acetate = nothing
2. Uncharged acetate + charged acetate = attracts
3. Charged acetate + charged acetate = repels
4. Charged acetate + uncharged vinyl = attracts
5. Charged acetate + charged vinyl = attracts
6. Charged vinyl + charged vinyl = repels
7. Uncharged vinyl + uncharged vinyl = nothing

Question 5

Static Electricity

Answer 5

• Build up of charges ion ones area waiting to be discharged
• Charges remain stationary

Question 6

Law of Charges

Answer 6

• Unlike charges attract
• Like objects repel
• Charged objects attract neutral objects
• Created by Benjamin Franklin

Question 7

Insulators

Answer 7

• Any material in which charge stays on spot when object is rubbed
• Does not conduct electric charges
• Holds electrons tightly
  Ex. cotton, glass

Question 8

Conductors

Answer 8

• Materials that allow electric charges to move freely
• Does conduct electric charges
• Holds electrons loosely
  Ex. copper, aluminum

Question 9

Fair Conductors

Answer 9

• Materials that allow electrons to move but not freely
  Ex. human body, carbon

Question 10

Semiconductors

Answer 10

• Materials with a higher conductivity than insulators but a lower conductivity than metals
• Conductivity is increased when foreign atoms are placed into pure material
  Ex. silicon with gallium added

Question 11

Superconductors

Answer 11

• Offer little if any resistance to the flow of charges
• Some materials may become superconductors when subjected to low temps
• Take up less space and can carry higher charges than normal conductors
  Ex. electric generators, high voltage power lines

Question 12

Neutralised

Answer 12

• Became balanced

Question 13

Electric Discharge

Answer 13

• Movement of electrons from place to place
• Can cause sparks
• Serious safety hazard as can shock people, damage equipment and cause explosions or fires

Question 14

Grounding

Answer 14

• Connecting an object to Earth with an conducting wire
• Earth supplies electrons needed to neutralize conductive materials

Question 15

Ionization

Answer 15

• Ionization devices produce positive and negative ions
• Ions are attracted to materials with an opposite charge
• Ions transfer charges until object is neutralized