V=IR
Where:- V=Voltage (v), I=Current (A), R=Resistance (
).F=ma
Where:- F=Force (N), m=mass (kg), a=acceleration (ms·²).
F=mg
Where:- F=Force (N), m=mass (kg), g=acceleration due to gravity (ms·²).
T=fd
Where:- T=Torque (Nm), f=force (N), d=distance (m).
W=fd
Where:- W=work done (or energy) (j), f=force (N), d=distance (m).
P=wt
Where:- P=Power (w), w=work done (or energy) (j), t=time (s).
Q=It
Where:- Q=quantity of electricity (c), I=Current (A), t=time (s).
þ=LA
Where:- þ=Resistivity (
m), L=Length (m), A=Area (ms·²).B=ΦA
Where:- B=Magnetic Flux Density (T), Φ=Magnetic Flux (mWb), A=Area (ms·²).
E=BLV
Where:- E=Induced emf (V), B=Magnetic Flux Density (T), L=Length (m), V=Voltage (ms·¹).
Where: Up=Primary Voltage (V), Ns=Secondary Turns, Us=Secondary Voltage (V), Ns=Primary Turns.
These two (2) Principles can be combined and described using the following formula:
Increasing the Area (csa) Decreases the Resistance.
Below, Is a better way to look at it...
Where:- Is=Current Amperes Secondary, Ip=Current Amperes Primary.
Below, Is a another way to look at it...
* Task: If you don't already know them, look up the symbols used in working out efficiency.
√R²+XL²=Vs
Where:- R²=Resistance Squared, XL²=Inductive Squared, Vs=Supply Voltage.
R=þl/a
Where:- E=Induced emf (V), B=Magnetic Flux Density (T), L=Length (m), V=Voltage (ms·¹).
R=þl/a
þ (rho) is the symbol used for Resistivity.
Remember:
Increasing the length, Increases the Resistance.
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