P2.1 Static and current electricity Flashcards
What is static electricity?
Electrical charge built up on insulating materials
What is another name for electrical charge?
Electrostatic charge
What is the charge of a proton?
+1
What is the charge of an electron?
-1
What particles does the nucleus of an atom contain?
Protons and neutrons
Why can’t protons be transferred when two insulating materials are rubbed together?
Protons are fixed in the nuclei of atoms
Which material gains electrons when you rub an acetate rod and a cloth together?
The cloth
Which material gains electrons when you rub a polythene rod and a cloth together?
The polythene rod
What happens when the charges of two objects are the same?
They repel each other
What happens if the charges of two objects are different?
They attract each other
What is induction?
When an object is charged by another charged object placed close to it
What is induced charge?
An electrostatic charge caused by another charged object being brought near
What does it mean when an object is discharged?
It no longer has a charge
What is the process of earthing?
Connecting something to earth so than an electrostatic charge can flow away
When can static electricity on everyday objects be dangerous?
When it can cause a spark as this could create fires
How can you prevent sparks being created from static electricity built up on objects?
You can make a conducting path to discharge the static electricity
What is a bonding line?
A metal wire used to connect aircraft to earth before it’s refuelled
What are some uses of static electricity?
Insecticide sprayers and electrostatic spray painting
Why does static electricity build up on insulating materials?
Any charge transferred to the material isn’t conducted away
Why can’t insulating materials conduct away electricity?
The electrons in insulating materials cannot move around
What type of current do cells and batteries supply?
Direct current
What is direct current?
A current that only flows in one direction
What is a current?
The rate of flow of charged particles
What type of current do generators produce?
Alternating current
What is an alternating current?
A current in which the electrons change direction many times each second
What does the size of a current depend on?
How much charge is passing through a point in the circuit each second
What is charge measured in?
Coulombs (C)
What is current measured in?
Amperes (amps, A)
What does Q = I x t stand for?
Charge = current x time
What is the relative mass of an electron in comparison to a proton?
0.0005
What is the charge of a neutron?
0
How do you create static electricity?
You rub two insulating materials together
