Q2 Answer all of the following parts (a), (b), (c), etc. (a) What is an electric current?
(b) State Joule’s law. (c) What is the difference between a.c. and d.c.?
(d) List two safety devices that are used in domestic electric circuits. (e) What will happen when a current of 20 A flows through a fuse marked 13 A? (f) What function does a miniature circuit breaker (MCB) serve in an electrical circuit? (g) What is the meaning of a rating of 30 mA on an RCD?
(h) An electric kettle has exposed metal parts. How is the risk of electrocution minimised? (i) Name a device that is often used nowadays in domestic electric circuits instead of fuses. (j) What is bonding?
(7) (7) (7) (7) (7) (7) (7) (7) (7) (7)
‘SECTION B’ FULL ‘STS’ QUESTION
Typical of Question 11 in Leaving Cert. Exam
Q3 Read the following passage and answer the following questions. Focus on safety Electricity is so much a part of modern living that we can often take it for granted.A powerful and versatile energy, electricity can be dangerous if it is not used properly.Although serious accidents with electricity in the home are rare in Ireland, each year there are a small number of serious injuries. Most of the accidents that occur are due either to carelessness or to a lack of awareness of some basic rules which should be observed in the use of electricity.
Electricity supply into your home The electricity supply into your home comes through the ESB main fuse and the ESB meter. Both of these items are sealed, and should never be touched by anyone other than ESB Network’s staff.
Any electrical installations from your ESB meter into your home (as opposed to those from the electricity network into your meter) are your responsibility.All repair work to electrical installations should only be carried out by a registered electrical contractor.
Know how to turn off the electricity in your home in case of emergencies.
Your distribution board Your distribution board is the central point of your home’s electrical system. It is also the point at which your electrical wiring divides to provide individual circuits for the various applications throughout your home, e.g. lighting, socket outlets, immersion heater etc.
