Physics P4

Sparks

Electrons

• An atom consists of a small positively charged nucleus surrounded by an equal number of negatively charged electrons
• In a stable, neutral atom there are the same amounts of positive and negative charges
• All electrostatic effects are due to the movement of electrons
• Like charges repel, unlike charges attract
• When a polythene rod is rubbed with a duster, electrons are transferred from the duster to the polythene, making the polythene rod negatively charged
• When a acetate rod is rubbed with a duster, electrons are transferred from the acetate to the duster, leaving the acetate rod positively charged
• An object has : 1) a negative charge to an excess of electrons. 2) a positive charge due to a lack of electrons
• Atoms or molecules that…