Sparks

Question 1

Recognise that insulating materials can become charged when rubbed with another insulating material

Answer 1

An insulating material can become electrically charged if it is rubbed with another insulating material. The charge is static electricity.

Question 2

Describe how you can get an electrostatic shock from synthetic clothing

Answer 2

Synthetic clothing can become charged up by the friction between the clothing and the persons body as they move and this makes the clothing cling. When the clothing is later removed, static sparks are sometimes produced.

Question 3

Describe how you can get an electrostatic shock if you become charged and then become earthed

Answer 3

Touching water pipes after walking on a floor covered with an insulating material e.g. Synthetic carpet

Question 4

Recognise that like charges repel and unlike charges attract

Answer 4

Two insulating materials:

• with the same charge will repel each other
• with different charges will attract each other

Question 5

Describe the static electricity in terms of the movement of electrons

Answer 5

• a positive charge due to lack of electrons

- a negative charge die to an excess of electrons

Question 6

Recognise that atoms or molecules that have became charged are ions

Answer 6

The atoms or molecules that have become charged are then called ions

Question 7

Explain how the chance of receiving an electric shock can be reduced by:

Answer 7

Correct earthing
Use of insulating mats
Using shoes with insulating soles
Bonding fuel tanker to aircraft

Question 8

Explain how anti-static sprays, liquids and cloths help to reduce the problems of static electricity

Answer 8

By preventing the transfer of charge from one insulator to another. With no build-up of charge, there can be no discharge

Question 9

Explain how static electricity can be a nuisance

Answer 9

• dirt and dust attracted to insulators (plastic containers, TV monitors etc)
• causing clothing to “cling”

Question 10

Explain how static electricity can be dangerous when:

Answer 10

• in atmosphere where explosions could occur e.g, inflammable gases or vapours or with high concentrations of oxygen
• in situations where large quantities of charge could flow through the body to earth

Question 11

State the two types of charge

Answer 11

Positive

Negative