Electricity and circuits

• A circuit is a pathway along which tiny particles carrying electric energy flow
• Static electricity= electrons do not move(stationary)
• Current electricity= electrons move
• Voltage is the force that drives an electrical current around a circuit.
• Law of electrostatic= like charges repel, unlike charges attract
• Advantages of static electricity= crop spraying, spray painting, finger printing, photo copy machine
• Disadvantages of static electricity= lightning strikes are fatal, build up of charges thus explosion at pumps, destroy sensitive equipment
• There are 2 types of static electricity: positive and negative charge
• Law of electrostatics

  like charges repel, unlike charges attract
• There are 2 types of Charges

  • Positive and negative charge
• How lightning is formed

  1. Clouds pass near each other

  2. Electric charges build up between thunderclouds or within a cloud

  3. Positive charges are attracted to negative charges on another cloud

  4. Charge jumps the space between the clouds causing a flash of lightning
• Lightning travels at the speed of light (3x10^8 m/s)
• Sound travels at 330 m/s
• Protecting buildings from lightning

  Install a conducting pole (lightning rod) at the highest point
• Positive charge= protons
• Things to avoid during a thunderstorm: don't stand under trees, avoid open fields, open water, hanging wires, standing under an umbrella
• You can make a simple circuit by using a cell, bulb and pieces of wire.
• Electric conductors: allow electrons to flow through a circuit easily
• Electrical insulators do not allow electron to flow through a circuit easily.
• Ammeter: measure current
• Voltmete- measures voltage: Connected parallel to the component you want to measure
• Resistance- the opposition to the flow of electrons in a circuit.
• Conventional current flow: flow of electrons from the positive terminal to the negnegative terminal( this is not the correct flow)
• Correct flow of electrons is from the negative terminal to the positive.
• Ohms law- Voltage(V) = Current(I) x Resistance(R)