ELECTRICAL CIRCUITS

Honelako gehiago

Project Managemant

Michael Carlson‑k egina

Elementary Ed. Mesurements

justin ruzicka‑k egina

revolution of modern science

heba hussein‑k egina

chapter3. SCIENTIFIC INQUIRY

jin shi‑k egina

ELECTRICAL CIRCUITS

MEASUREMENTS

CURRENT

flow of electrons

measured by: ammeter

units: ampere(A)

POWER

definition: energy used per second

units: watts(W)

VOLTAGE

measured by: voltmeter

connected in parallel

units: volts(V)

components

DIODE

current only flows when voltage is greater than 0.6v

BULB

curve

RESISTOR

straight line

series - parallel current: all components are connected end to end to form only one path for the current to flow through the circuit.

For example: multiple bulbs are connected with wire and also some are in the loop

used for: voltage dividers

parallel circuit: it is a circuit that comprises branches that the current divides and only part of it flows through any branch.

example: light fixtures that use multiple bulbs.

used for: to keep electricity flowing when one pathway is interrupted.

series circuit: it is a circuit comprises a path along which the whole current flows through each component.

examples: often lawnmowers have two switches in series with each other so both need to switch before the mower will turn on.

used for: it provides exactly one path between any two points for electric current.

TYPES

series parallel circuit

PARALLEL CIRCUIT

SERIES CIRCUIT

LAWS OF ELECTRIC CIRCUIT:

KVL LAW

ENTERING CURRENT AT NODE IS EQUAL TO LEAVING CURRENT AT NODE.

KCL LAW

THE ALGEBRAIC SUM OF VOLTAGE AT NODE IN A CLOSED CIRCUIT IS ZERO.

OHMS LAW

CURRENT THROUGH A CIRCUIT IS PROPORTIONAL TO THE VOLTAGE ACROSS THE CONDUCTOR

KIRCHHOFS LAW

RESIDUAL CURRENT DEVICE: compares current in live and neutral wires. used in gardens.

MINIATURE CIRCUIT BREAKER: it replaces fuses. electromagnets used in it. melts if the current is too big.

no protection against electric shock.

FUSE: melts if current is too big

no protection against electric shock

EARTH LEAD: current directly flows straight to earth.

protects against electric shocks

PLUG

INSULATION

black

NEUTRAL

blue

EARTH

green and yellow

LIVE

fuse

brown

Example: battery, lamps, generators, and so on.

it can be defined as the path for transmitting electric current.