Sparks Electrical News April 2015

people on the move 28

Bright Sparks

Royal HaskoningDHV

ifmelectronic SA

Voltex

Amixed collection Tommy's collection of pets was his pride and joy. He had snakes, several birds, rabbits and also some cats. Altogether his entire collec- tion of animals had 15 heads, six wings and 38 legs. Howmany snakes did he keep?

March solution

Cornel Swart, field sales engineer, Centurion.

Albert Louw, product specialist, mobile control systems, Centurion.

Stuart Munstermann, field sales engineer, Durban branch.

Salani Sithole, managing director, South African operations.

Jacques vanWyngaard, sales manager, Free State Admin branch.

A tower of coins The simplest way to solve this puzzle is to solve the same puzzle with fewer coins, and then work up to four coins. Tomove one coin takes of course, just one move

Tomove two coins takes three moves like this

Tomove three coins takes sevenmoves like this

In this diagram, the moves have been abbreviated to show that all you have to do is move the top two coins (which you know takes three moves); thenmove the third coin (one move); and finally, move the top two coins again (another three moves). Now the pattern is easier to see. Tomove four coins, you first move the top three coins (sevenmoves). Then move the fourth coin (one move) and thenmove the top three again (sevenmore moves) – a total of 15 moves. The number of move required for four coins is one more than double the number required for three coins. By the same pattern, the number of moves required tomove five coins would be 15 + 1 +15 = 31

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Energy management, load management, load shedding, load control devices, meters, transducers, lamps, lighting control, timers, water heating, time-of-use tariffs, power factor correction, relays, heating, ventila- tion, air conditioning, control gear, alterna- tive energy. Enclosures, earth leakage devices, circuit breakers, fuses, surge and lightning protec- tion, metering switches, dimmers, sockets, disconnectors, Certificate of Compliance, testing and measuring instruments, tools and accessories, cabling glands, flameproof. DISTRIBUTIONBOARDS, SWITCHES, SOCKETSANDPROTECTION Editor: Erika van Zyl Consultant: Ian Jandrell PrEng, BSc(Eng), GDE, PhD, FSAIEE, MIEEE Production & layout: Colin Mazibuko

Advertising: Carin Hannay Managing member: Jenny Warwick Publisher: Karen Grant Published monthly by: Crown Publications cc P O Box 140

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april 2015

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