Static Electricity

Question 1

what is static electricity

Answer 1

charges that are not free to move, which causes them to build up in one place and often ends with a spark or shock when they are finally able to move

Question 2

build up of static is caused by what

Answer 2

friction

Question 3

what happens with a polythene rod and a cloth duster when rubbed together

Answer 3

electrons move from the duster to the rod, rod becomes negatively charged and the duster is left with an equally positive charge (vice versa for an acetate rod)

Question 4

1) when two … materials are … together, electrons will be … and … on the other
2) this’ll leave a … electrostatic charge on one and a … electrostatic charge on the other
3) which way the electrons are transferred depends on the … involved
4) electrically charge objects … small objects placed near them

Answer 4

insulating
rubbed
positive
negative
two materials
attract

Question 5

positive and negative electrostatic charges are only ever produced by the movement of ..

Answer 5

electrons (positive charges dont move)

Question 6

a positive static charge is always caused by electrons ..

Answer 6

moving away elsewhere

Question 7

how can a charged conductor be discharged safely

Answer 7

by connecting it to earth with a metal strap, the electrons will flow down the strap tot the ground if the charge is negative and flow up the strap from the ground if the charge is positive

Question 8

what is the rate of flow of electrical charge called

Answer 8

electric current

Question 9

as charge builds up, so does the … (causing sparks)

Answer 9

voltage

Question 10

the greater the … on an … object, the greater the .. between it and the earth. if the voltage gets … there’s a … which … across the gap

Answer 10

charge
isolated
voltage
big enough
spark
jumps

Question 11

like charges ..

Answer 11

repel

Question 12

opposite charges…

Answer 12

attract

Question 13

experiment to test whether a rod of material is charge

Answer 13

1) suspend a rod with a known charge on a thread and see if there is repulsion or attraction when the rod you’re testing is brought close to it
2) if there is an attraction, then the test rod has the opposite charge to the suspended rod
3) if there is a repulsion, then the test rod has the same charge as the suspended rod

Question 14

how an inkjet printer works with static electricity:

1) tiny droplets of ink are forced out of a … making them …
2) the droplets are… as they pass between two metal plates. a … is applied to the plates - one is … and the other is …
3) the droplets are … to the plate of the … charge and … from the plate with the … charge
4) the … and … of the voltage across each plate changes so each droplet is deflected to hit a … on the paper
5) loads of tiny dots make u your printout

Answer 14

fine nozzle
electrically charged
deflected
voltage
negative
positive
attracted
opposite 
repelled 
same
size
direction 
different place

Question 15

how a photocopier works with static electricity:

1) the … is positively charged. an image of what you’re copying is projected onto it
2) whiter bits of what you’re copying make … fall on the plate and the charge … in those places
3) the charged bits attract negatively charged … which is transferred onto positively charged paper
4) the paper is … so the powder sticks

Answer 15

image plate
light
leaks away
black powder
heated

Question 16

why do some synthetic clothes crack when you take them off

Answer 16

when this type of clothe are dragged over each other i.e. tumble dryer, electrons gets scraped off, leaving static charges on both parts, and that leads to the inevitable attraction and little sparks/shocks as the charges rearrange themselves

Question 17

lightning:
rain drops and ice … inside storm clouds, knocking off electrons and leaving the top of the cloud positively charged and the bottom of the cloud … this creates a … and a …

Answer 17

bump together
negative
huge voltage
big spark

Question 18

fuel-filling nightmare:

1) as … flows out of a filler pipe, …
2) this can easily lead to a … and in .. or .. places - BOOM
3) make the nozzles out of … so that the charge is … instead of building up
4) it’s also good to have … between the … and the …

Answer 18

fuel
static can build up
spark
dusty
fumy
metal
conducted away
earthing straps
fuel tank
fuel pipe