3.3 Flashcards
How does an electrical charge occur?
Deficiency of electrons at one point and excess of electrons at another point.
What is the electrical charge?
The sum of all electrical charges.
What is the symbol of charge?
Q.
What is the formula for current?
Current (I) = Charge (Q) / Time (t)
What is the unit of charge?
Ampere-second.
What are the 6 methods of generating voltage?
Induction Chemical Heat Light Crystal deformation Friction
What is induction?
If a coil enters the magnetic field of a magnet, an electrical voltage is generated in the coil during the movement.
What is electrolysis?
When 2 pieces of metal are immersed into an electrical conducting liquid, and a voltage is created between the 2 electrodes.
What is an example of an electrically conducting liquid?
Water with added sulphuric acid.
What is heating to emit electrons known as?
Thermionic emission.
On what materials can light result in a charge separation?
Some semi conductors (silicon or germanium)
How is a voltage created using pressure?
When a Piezo crystal is deformed using pressure
Piezoelectric effect
When would sparking occur between 2 bodies of different charge?
If the electrical field between them is concentrated at its edges.
What is the primary reason for static dischargers?
Electrical field concentrated at edges causing sparks.
What is conventional current flow?
Electric current flows for positive to negative pole.
What is the flow from negative to positive pole called?
Electron flow
Physical current flow
What charges move in metals?
Only negative.
What is 1 coulomb equal to?
1 ampere-second.
What does the direction of electrons flowing through a conductor depend on?
Polarity of applied voltage.
What is electrons constantly flowing in 1 direction called?
DC
What is a current that periodically changes it’s flow direction?
AC.
What components of tap water decompose when a DC is applied?
Hydrogen at negative pole.
Oxygen at positive pole.
What is the conducting substance during electrolysis called?
An electrolyte.
What gases are filament light bulbs filled with to prevent the filament from burning, oxidising or vaporising?
Nitrogen, argon or krypton.
