# Will these lightbulbs light up?

1. Jun 25, 2009

### Max CR

This is part of a project I am working on. It is not related to school.

Figure One

The block is a 9 volt battery. The circle is the lightbulb. The wires goes from the battery to the lightbulb. Between the lightbulb and the battery the two wires connect. Will the lighbulb still light?

Figure Two

The block is a 9 volt battery. The circle is a lightbulb. The wires go from the battery to the three lightbulbs. Between the lightbulbs and the battery, the wires connect at the indicated places. Will the lightbulbs still light? Will the lightbulbs light evenly? Will the lightbubls light at the same time?

Thank you. Please only give real answers since this is an important question.

2. Jun 25, 2009

### mgb_phys

No
Yes,Yes,Yes (assuming that the wires don't touch where they cross - this isn't exaclty a standard circuit diagram drawing)

Are you interested in the reasons?

3. Jun 25, 2009

### Staff: Mentor

For the second, as long as they only join in the two points at the bottom and not where the lines cross, that's just a clumsily drawn parallel circuit and will work fine.

4. Jun 25, 2009

### Staff: Mentor

What kind of important project is this? It would help us to give you real answers if you put the question in context.

Also, there generally are no "light bulbs" for 9V batteries (Quiz Question -- why?)

And why in the world would you ask if the shorted out battery in the first figure will still light a "light bulb"? Makes no sense.

5. Jun 25, 2009

### Max CR

THank you. Being that these wires will actually CONNECT in the diagram, I thought that where the wires cross/connect to eachother that this may be a problem. It turns out that it is. I will have to put insillation around these wires. Thanks again!

6. Jun 25, 2009

### mgb_phys

You do know that the first diagram will destroy the battery - and possibly start a fire?

7. Jun 25, 2009

### Staff: Mentor

Uh, most wires come with insulation....you can buy some!