Static electricity

Question 1

How can an insulator be charged by friction?

Answer 1

• When insulating materials rub together, electrons will be taken off one and moved to the other
• The buildup of charge is called static electricity. Buildup occurs because electrons don’t move in insulators
• The object gaining electrons becomes negatively charged
• The object losing electrons becomes, equally positively charged

Question 2

How does rubbing a balloon in static work?

Answer 2

• Rubbing a balloon against hair moves electrons to the balloon
• If you put this on the wall, the negative charges in the balloon repel the negative charges in the wall
• This leaves a positive charge on the surface
• Attracts balloon

Question 3

How does using a comb in static work?

Answer 3

• Electrons transferred to comb
• Can be used to pick up bits of uncharged paper
• Attracts paper due to static induction

Question 4

How is sparking and shocks caused due to static

Answer 4

• Sparking occurs when enough charge builds up between the two objects, but they are not touching.
• This causes the electrons to jump between the gap, causing a spark
• Electrons can also jump to earthed conductors, like humans, causing a static shock

Question 5

How does earthing work in static?

Answer 5

• Sparks can be prevented by connecting a charged object to the ground using a copper wire.
• This allows electrons to flow to the earth, removing excess charge.

Question 6

How is static used in insecticide spray?

Answer 6

• When sprayed, the particles are given a charge, causing them to repel and spread evenly.
• The plants being sprayed are charged by induction so the insecticide sticks.

Question 7

Dangers of static in fuelling cars

Answer 7

• As fuel flows out of the filler pipe, static builds up
• This can lead to a spark if the charge is too high
• This can cause an explosion in places where there is lots of fumes, such as a petrol station
• This can be stopped by earthing the hoses

Question 8

What is an electric field?

Answer 8

region where an electric charge fields a force

Question 9

Describe the shape and direction of an electric field around a point charge

Answer 9

• In a positive charge, the field points outwards in all directions at right angles to the surface
• In a negative charge, the field lines point towards the charge
• Closer the lines, stronger the field

Question 10

Shape and direction of electric field between parallel plates

Answer 10

• The field lines go from positive to negative
• The strength and direction of field is same everywhere between two plates except at the very ends
• When the lines join up, the plates are attracted to each other

Question 11

How do electric fields explain sparking?

Answer 11

• When an object is charged, it generates an electric field
• When a charged object has a high potential difference between the charged object and the earth, it creates a strong electric field
• A strong electric field can ionise air particles to make them positively charged
• This allows air to become a conductor, and electrons pass through it.

Question 12

what is potential difference in dumbfuck simple terms

Answer 12

• difference in charge