Electricity Flashcards
Which particles are in the nucleus of the atom?
Protons and neutrons
What happens if two positive charges are brought together?
They repel each other
What happens if two negative charges are brought together?
They repel each other
What happens if a positive and a negative charge are brought together?
They attract each other
What is electric charge?
An electric charge occurs when there are fewer or more electrons than protons.
Name one place that electrostatics can be used.
Laser printers
Paints spraying
Cling film
Forensic science
Dust removal
Electrostatic precipitators
Electrostatic separators
What does an electric field line show?
The direction a positive charge would move in that field.
Explain how electrostatics can be used in paint spraying a car.
Car is connected to a negative terminal so that it is negatively charged.
Spray gun is made positively charged so the paint particles are positive.
The poistive paint is attracted to the negative car.
Areas of the car already covered in paint will repel any more charged paint.
What is the effect of an electric field on a charge?
The charge will experience a force.
What would the field lines around a positive point charge look like?
Field lines show direction away from the positive point charge.
What would the field lines around a negative point charge look like?
Field lines show direction towards the negative point charge
What would the field lines look between parallel plates?
Field lines run from positive to negative plate, with a bulge at the ends of the parallel plate.
How can you indicate a stronger electric field?
More field lines
How can you indicate a weaker electric field?
Fewer field lines
How is a uniform electric field represented?
Evenly spaced field lines
What would happen to an electron being fired through the electric field below?
It would experience a force and be attracted to the positive plate
What is current?
The charge transferred per second
What is d.c.?
Direct current. Charges move in one direction only.
What is a.c.?
Alternating current. The charges change direction constantly
Name one source of d.c.
A battery
How can you tell from this oscilloscope image that this is a.c.?
(its wavey)
The trace shows a change in direction
Name one source of a.c.
Mains supply
What type of current is represented by this oscilloscope image?
(its a straight line)
d.c.
What type of current is represented by this oscilloscope image?
(its wavey)
a.c.