uses of electrostatics Flashcards
how does a paint sprayer work?
it charges paint drops, they spread out which gives them coverage
how do crop sprayers on farms work?
the fertiliser particles are charged to give them coverage
what are electrostatic dust precipitators used for?
to remove the dust or soot in smoke
how do electrostatic dust precipitators work?
charged plates are placed inside chimneys to attract soot particles
how does a defibrillator work?
by discharging a charge, it delivers a controlled electric shock through a patients chest to restart the heart
explain in a technical term how electrostatic dust precipitators work?
metal plates and a grid (rods) are put into a chimney.
They are connected to a high voltage supply so that the grid becomes negatively charged.
The plates are earthed and gain the opposite charge to the grid.
As the dust particles pass the grid they become negatively charged by an addition of electrons, meaning the dust particles get attracted to the plates as they are unlike charges.
at intervals the plates vibrate and the dust falls into a collector
what is dust used to make?
building blocks
explain in a technical way how a paint spray works?
the spray gun is charged.
all the paint particles become charged with the same sign of the gun.
like charges repel so the paint particles move away from each other giving a fine spray.
The object to be painted is given the opposite charge to the paint.
This means the paint is attracted to the object.
explain in a technical way how defibrillators work?
two paddles are charged from a high voltage supply typically 300-1000 V.
They are then placed firmly onto the chest to ensure a good electrical contact. A conducting gel is usually applied before hand.
An electric charge is passed through the patient to make their heart contract.
how is a defibrillator adapted to not give the doctor a shock?
the paddles have insulated plastic handles
how much energy does a defibrillator supply normally?
about 400 J of energy in a few millisecons
how can the power from a defibrillator be calculated? (equation)
power= energy (divided) time
what is an implantable defibrillator?
a small battery- powered device implanted under the skin in the upper part of the chest wall and is connected to the heart.
what does it monitor?
heart rhythm and senses if there is about to be a severe disturbance in heart rhythm
what does it do if it senses anything unusual in the heart rhythm?
it delivers an electrical impulse to the heart to stop abnormal rhythm. It can deliver up to four consecutive discharges of 25 J to 30 J
