##### Document Text Contents

Page 8

Electrical Formulas, Explanations

Impedance (Z)

Impedance is the total opposition to an alternating current presented by a circuit (OHMS). Total AC

resistance.

Amperes

Volts

I

E

Z == , ( ) 22)(Im CL XXRZpedance −+=

Power factor (PF)

Power factor (Pf) equals the cosine, where θ is the angle is either lead or lag.

Z

R

EI

P

werApparentPo

TruePower

PF ===

TRIGONOMETRY

Trigonometry is the mathematics dealing with the relations of sides and angles of triangles. A triangle is a

figure enclosed by three straight sides. The sum of the three angles is 180 degrees. All triangles have six

parts: three angles and three sides opposite the angles. Right triangles are triangles that have one angle of

ninety degrees and two angles of less than ninety degrees.

Hypotenuse

deOppositeSi

Sine =θ

Hypotenuse

deAdjacentSi

CoSine =θ

deAdjacentSi

deOppositeSi

Tangent =θ

deOppositeSi

deAdjacentSi

CoTangent =θ

deAdjacentSi

Hypotenuse

Secant =θ

deOppositeSi

Hypotenuse

CoSecant =θ

Note: θ = Theta = any angle

Remember: SOHCAHTOA, Sine, opposite, hypotenuse, cosine, adjacent, hypotenuse, tangent,

opposite, adjacent.

Page 8 of 16

ADJACENT SIDE

HYPOTENUSE

O

P

P

O

S

IT

E

S

ID

E

60º

90º30º

“Y”

“X”

ALWAYS PLACE THE ANGLE TO BE SOLVED AT

THE VERTEX (WHERE “X” AND “Y” CROSS).

Electrical Formulas, Explanations

Impedance (Z)

Impedance is the total opposition to an alternating current presented by a circuit (OHMS). Total AC

resistance.

Amperes

Volts

I

E

Z == , ( ) 22)(Im CL XXRZpedance −+=

Power factor (PF)

Power factor (Pf) equals the cosine, where θ is the angle is either lead or lag.

Z

R

EI

P

werApparentPo

TruePower

PF ===

TRIGONOMETRY

Trigonometry is the mathematics dealing with the relations of sides and angles of triangles. A triangle is a

figure enclosed by three straight sides. The sum of the three angles is 180 degrees. All triangles have six

parts: three angles and three sides opposite the angles. Right triangles are triangles that have one angle of

ninety degrees and two angles of less than ninety degrees.

Hypotenuse

deOppositeSi

Sine =θ

Hypotenuse

deAdjacentSi

CoSine =θ

deAdjacentSi

deOppositeSi

Tangent =θ

deOppositeSi

deAdjacentSi

CoTangent =θ

deAdjacentSi

Hypotenuse

Secant =θ

deOppositeSi

Hypotenuse

CoSecant =θ

Note: θ = Theta = any angle

Remember: SOHCAHTOA, Sine, opposite, hypotenuse, cosine, adjacent, hypotenuse, tangent,

opposite, adjacent.

Page 8 of 16

ADJACENT SIDE

HYPOTENUSE

O

P

P

O

S

IT

E

S

ID

E

60º

90º30º

“Y”

“X”

ALWAYS PLACE THE ANGLE TO BE SOLVED AT

THE VERTEX (WHERE “X” AND “Y” CROSS).