Simple Electric Circuit

The Simple Electric Circuit will help you to learn the basic concepts of electricity and electrical circuits. You will experience and build a light circuit powered by a battery and controlled by a switch. You will also learn about electrical conductors and insulators. You may use your kit in connection with your science project or you may just try it as an educational activity or technology project. If you are doing a science project, you will need additional materials to complete your project.

Check the content of your kit. The Simple Electric Circuit Kit includes:

• Wooden base to mount the circuit
• 2 Light Bulbs (1.2 Volt)
• 1 lamp holder
• 1 Battery holder (for D size battery)
• 1 Simple Switch (Known as knife switch)
• Screws used to mount the switch and the lamp holder
• Insulated solid copper wire (Gage 22)
• Adult Supervision is required (but not included!)

Make a Simple Electric Circuit

Introduction:

A Simple Electric Circuit is a circuit including a power source (battery), a resistor (light bulb) and a switch connected to each other in series (meaning that wires connect the battery to the switch, the switch to the light bulb and the light bulb back to the other end of the battery).

Connection of wires to the battery holder, switch and the lamp base are usually done using the screws or clips. You can use household tools such as a pair of scissors to cut the wire and remove the insulation from the contact points. You will also need a D size battery to power your circuit.

Instructions:

Use the picture bellow to see how you must mount the components on the board. Use small mounting screws to mount the battery holder, the switch and the lamp holder to the appropriate places on the board. A screw driver and assistance of an expert adult may be required.

Loosen the contact screws (not mounting screws) on the lamp holder and on the switch to make them ready for connecting the wires. Cut 3 pieces of wire (any color) to 7", 5" and 4". Remove the insulation from 1/2 inch of each end of the wires. To do that first make a cut on the plastic insulation all around the wire. Then pull the insulation out. Use the 7" ling wire to connect the battery holder to the one of the contact screws on the lamp holder. Use the 5" long wire to connect the remaining contact screw of the lamp holder to one of the screws on the switch Use the 4" long wire to connect the remaining screw on the switch to the remaining clip of the battery holder.

These pictures on the right show how you connect and secure the wire to the battery holder clips. Simply push the spring, insert the wire and then release the spring. (Handle the clips with care because they may come off with excess force) To connect the wires to the screws on the lamp holder or the switch, first bend the end of the wire like U shape and then hook them under the screw, and then tighten the screw. Warning: 1. No electrical contact will be made if you have not removed the insulation from the ends of the wire. 2. Do not use flame to remove the insulation. Doing this is dangerous and will blacken the ends of the wire.

Test your circuit:

Insert the battery, screw a light bulb into the lamp holder and close the switch. The light bulb must light up. If it does not check all the contacts and try again. You may also need to check the battery and the light bulb.

The circuit or switch is open, The light is off.	The circuit or switch is closed, The light is on.

Opportunities for Science Projects
You may use your kit in relation to many different science projects. Construction of a simple electric circuit by itself may be used as a science project for many different grades. You may also use some color paper to make a nice lamp shade for it and use it as your night light. Some other students may need to use their completed circuit to do further research for their science project. Two common project ideas that use this kit are:

1. Can electricity create heat? To do this project you will also need a thermometer to show that the light bulb is getting hot.
2. Identify conductors and insulators around you. It is important to know what materials are conductive and what materials are not. The test is simple. Open the switch and place the object between the poles of the switch. If the light comes on, then the object is conductive. You may try this with metals (coins, paper clips, nails, etc.) and non-metals (glass, plastic, stone, wood, etc.)

These two experiments are described bellow:

Experiment 1: Can electricity create heat?

Introduction: Electricity and heat are two different types of energy. In physics we learn that energy cannot be destroyed. It can only be converted to other types of energy. In this project we intend to show that electrical energy can be converted to heat. For this experiment you will use your simple electric circuit, a glass thermometer and a clock that can show seconds.

Procedure:

Make sure the switch is open and the light is off. Place the bulb of a glass thermometer on the top of your light bulb and cover both with black electrical tape so that the light cannot leak out. Let this sit at room for 10 minutes to make sure that everything is at room temperature. Record the temperature shown on the thermometer, set your clock and turn on the switch on the top of the hour. Read and record the temperature every 60 seconds (one minute). Your data table may look like this:

Experiment 2: Identify conductors and insulators around you. or

What Materials are Conductors of Electricity?

Introduction: By learning about conductors and insulators we can keep ourselves and our electrical equipment safe. Every year thousands of children and adults around the world are electrocuted because they did not use proper insulation while contacting with electrical wires or equipment. So much loss of life is a clear signal that every one must learn about electricity and safeguarding it by using insulators. This experiment is a fundamental step toward such education.

Procedure: Make sure the switch in your simple electric circuit is open and the light is off. Then place different objects between the poles of the switch one at a time. If placing the object between the poles of the switch can close the circuit and the light bulbs turns on, then the object is conductive. If the light does not come on, then the object is an insulator. Some of the objects you may try are: Coins, nails, gold and silver pieces, paper clips, safety pins, Pencil and the pencil's lead, rubber, wood, plastics, glass and aluminum foil.

Your results table may look like this:

Warning: The voltage (electrical power) of a battery (also known as dry cell) is usually about 1.5 Volts. When a material is insulator for 1.5 volt, it may be conductive for higher voltages. Even air is conductive for high voltages. You must be more careful as you start experimenting with higher voltages in future.

Why don't the birds get killed when they sit on high voltage electrical cables?

This is a common question for those who know "most high voltage electrical cables have no insulation.". The answer is simple. High voltage electricity can kill if it passes trough your body. When birds sit on the power cable, the electrical current cannot pass trough their body because no part of their body is touching the ground or any other wire. With the same token, someone wearing thick rubber shoes may touch a 110 volt electrical cable with one hand and stay safe; however, the same person may get electrocuted if he is touching a moist concrete wall or a water pipe with his other hand. For very high voltages such as 6000 volts, no insulation can protect us and we must stay at least 5 feet away from such high voltage cables. (That is why such cables don't have any insulation on them).

If you do not have this kit or the materials to complete your project, you can buy them online. Order early so you can save on shipping charges.