Unit 202 Flashcards
I relates to what?
Current in Amperes
Q relates to what?
Charge transferred in Coulombs.
t relates to what?
Time in seconds
What is the formula…
Q=It, or I=Q/t
Q=It
How many Coulombs per time period (t) at a particular current (I)
I=Qt
What current is produces when an amount of Coulombs move through a conductor in a specified amount of time (t)
What is a Coulomb?
1 coulomb is 6.7 times 10 to the power of 18 electrons moving through a conductor.
1A is equal to 1Q per second.
How many Coulombs if there is a charge of 3A over 32 seconds.
Q=It
I = 3
T=32
3x32=96C
What charge is produced by 834 Coulombs in 2 minutes?
I=Q/t
Q=834
t=120
834/120=41.7A
What is the definition of EMF (Electro Motive Force)
The number of Joules (J) of work require to move 1 C of electricity around a circuit.
This unit inis referred to as a Volt (V)
1V = 1 Joule/ 1 Coulomb
Q=It
W=QxV
If a battery of 12V gives a current of 5A for 10 minutes the amount of energy provided over the 10 minute period is?
W=QxV Q=It = 5x (10x60)C Q=3000C W=QxV = 3000x12 W= 36000 J or 3.6 kJ
What are the three effects of electrical current?
Thermal (Heating)
Chemical
Magnetism
What are the quantity and unit symbols for current?
Quantity = I Unit = A
What are the quantity and unit symbols for length?
Quantity = l (lower case L) Unit = m
What are the quantity and unit symbols for luminous intensity?
Quantity = I (upper case i) Unit = cd
What are the quantity and unit symbols for mass?
Quantity = m Unit = kg
What are the quantity and unit symbols for temperature?
Quantity = T Unit = K (kelvin)
What are the quantity and unit symbols for time?
Quantity = t Unit = s (second)
What are the quantity and unit symbols for area?
Quantity = A Unit = m2 (metres squared)
What are the quantity and unit symbols for capacitance?
Quantity = C Unit = F (farad)
What are the quantity and unit symbols for charge?
Quantity = Q Unit = C (coulomb)
What are the quantity and unit symbols for energy (work)?
Quantity = W (watt) Unit = J (joule)
What are the quantity and unit symbols for force?
Quantity = F Unit = N (Newton)