PHY 02 Lesson 3: Current, Resistance, Voltage

ELECTRIC CURRENT

flow of electric charges/electrons

The velocity of this motion is known as drift velocity.

If this flow is regulated and made to move continuously in one direction, then the flow becomes an

Electric potential energy

can be transferred to electrons because of electric field around the negative charges.

I = 𝒒/𝒕

ELECTRIC CURRENT Equation

I

the electric current

q

is the amount of charges that pass through a conductor

t

is the unit of time

Resistance

the ability of a material to oppose charge flow

ratio of potential difference to current

𝑅 = 𝜌𝐿/𝐴

Resistance Equation

R

resistance

p

is the resistivity of the conductor

L

is the length

A

is the cross-sectional area

ELECTRIC POWER

rate at which electrical energy is converted to other forms

P = IV

current times potential difference

measured in watts (W) watts = J/s

potential difference

measured in volts (V)

volts = J/C

electric current

measured in amperes (A) amperes = C/s

resistance

resistance

measured in ohms (2) ohms = V/A

electric power

measured in watts (W) watts = J / s

ELECTRIC CIRCUITS

The pathway for the current to move from the energy source to the appliances.

Open Circuit

Closed Circuit

Two Main Types of Electric Circuits

Open Circuit

Have gap/s where current cannot flow.

Closed Circuit

Functional circuit that has a closed loop. It allows the current to flow from the source of the current to the load.

SERIES CIRCUIT

All components are connected using a single pathway or single loop for current to flow

PARALLEL CIRCUIT

It is a has two or more paths for current to flow through.