what do you need to apply across a bulb
to cause a current to flow through it
Answers
An electric circuit is an unbroken path along which an electric current exists and/or is able to flow. A simple electrical circuit consists of a power source, two conducting wires (one end of each being attached to each terminal of the cell), and a small lamp to which the free ends of the wires leading from the cell are attached.
When the connections are made properly, the circuit will “close” and current will flow through the circuit and light the lamp.
Simple Circuit
A simple electrical circuit
Once one of the wires is removed from the power source or a “break” is made in the flow, the circuit is now “open” and the lamp will no longer light.
In practical application, circuits are “opened” by such devices as switches, fuses, and circuit breakers. Two general circuit classifications are series and parallel.
The elements of a series circuit are connected end to end; the same current flows through its parts one after another.
Series Circuits
In a series circuit , the current through each of the components is the same, and the voltage across the components is the sum of the voltages across each component.
Series Circuit
An example of a Series Circuit
Parallel Circuits
In a parallel circuit, the voltage across each of the components is the same, and the total current is the sum of the currents through each component.
If two or more components are connected in parallel they have the same potential difference ( voltage) across their ends. The potential differences across the components are the same in magnitude, and they also have identical polarities. The same voltage is applicable to all circuit components connected in parallel.
If each bulb is wired to the battery in a separate loop, the bulbs are said to be in parallel.
Parallel Circuit
An example of a Parallel Circuit.
The Voitage appled across a bulb causes a current to flow through it.
Hope this helps u.