circuit lab formulas

Question 1

Ohms law

Answer 1

V= IR

Question 2

Power

Answer 2

VxI
I² x R
v²/r

Question 3

Energy

Answer 3

E= P xt
energy: joules
p: watts
t: time seconds

Question 4

Voltage Division

Answer 4

Formula: V₁ = (R₁ / Rₜ) × Vₜ
Used for: Used to calculate voltage across a resistor in a series circuit.
Variables:
- V₁: Voltage across resistor R₁
- R₁: Resistor of interest
- Rₜ: Total series resistance
- Vₜ: Total voltage

Question 5

Current Division (2 resistors)

Answer 5

Formula: I₁ = (R₂ / (R₁ + R₂)) × Iₜ
Used for: Calculates current through one resistor in a parallel pair.
Variables:
- I₁: Current through R₁
- R₁, R₂: Parallel resistors
- Iₜ: Total current

Question 6

Current division for one resistor

Answer 6

Ii= IT(Rt/Ri)

Question 7

charge

Answer 7

Formula: Q= C x V
Variable:
- Q: charge
- C: Capacitance → needs to be farads not microfarads→ multiply by 10^-6
V: Voltage
Formula: Q = I × t
Used for: Calculates the electric charge transferred.

Question 8

Quantization of electrical charge

Answer 8

Q (Total charge)
measured in coulombs
n (number of electrons/elementry charges)
e (elementry charge)
~1.602x10^-19 C.

Question 9

Resistivity

Answer 9

Formula: R = ρ × (L / A)
Used for: Relates resistance to material properties and dimensions.
Variables:
- R: Resistance (Ohms)
- ρ: Resistivity (Ohm·meters)
- L: Length (meters)
- A: Cross-sectional area (m²)

Question 10

Emf equation

Answer 10

E= V +Ir
where r is the internal resistance