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Popular Mechanics South Africa

Popular Mechanics South Africa January/ February 2020

The South African edition of Popular Mechanics was launched in 2002 and has fast become the acknowledged voice of science and technology in South Africa. Underpinning its rich sci-tech content is an ever-changing mix of articles covering everything from automotive news and outdoor adventures to DIY projects. In essence, it explains how our world works

Paese:
South Africa
Lingua:
English
Editore:
RamsayMedia (PTY) Ltd
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12 Numeri

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6 minuti
letters

WRITE TO US • popularmechanics@ramsaymedia.co.za WINNING LETTER Heavy lifting I am a 72-year-old retired millwright and am writing in to comment on the article about elevators that ran in the November 2019 issue. I was employed during the ’70s as a senior trade-test officer at the then Central Organisation for Trade Testing, and one of the trades we tested was that of a lift mechanic. In those days, computers and even PLCs (programmable logic controllers) were still a pie in the sky and everything was done manually with relays and timers. You can imagine what chaos it was to figure out when what relay must activate, and for how long. We had the opportunity to take a ride on top of the high-speed elevators in the Carlton Centre in Joburg, and I can…

2 minuti
time machine

1 JANUARY 1941 Army’s ‘Big Bertha’ Cameras Map Huge Areas Kicking off the new year sky high, we brought you the story of ‘Big Bertha’, a one-metre focal camera used by the US military to photograph and map terrain from an aeroplane. Flying at a height of 6.5 km, the plane was equipped with electrical heating so that pilots and photographers could operate Big Bertha in comfort while peering out of an open window. 2 JANUARY 1929 How Fast Can A Man Fall? In the late ’20s many questions were being asked about what the maximum velocity of a person falling from a high altitude would be and whether they’d remain conscious. We presented testimonials from airmen who’d parachuted and the military’s response to their experiences. In addition, we conducted experiments and answered those questions. 3…

1 minuti
the bigger picture

PERCHED AT about 302 m above sea level, the lower station of the Table Mountain Aerial Cableway is the gateway to the mountain’s summit, at 1 067 m. Construction was completed in 1929 and the cableway has undergone many improvements since then. Using a jig-back system – one cabin will always move up the mountain while the other moves down, creating a counterbalance – the cabins weigh approximately 11 tons each including the fixed hanging gear. The cabins are suspended on track cables while the haul and heel cables pull the cabins up and down. The haul cable is driven and controlled at the lower station with a bull wheel, which is powered by a 540 kW electric motor via a reduction gearbox. The haul and track cables have a combined…

3 minuti
how your world works

Cycling a wave of coffee MAKING A CUP of coffee couldn’t be easier using Nespresso’s capsules – small aluminium pods that you simply pop into a machine. But along with this convenience comes the issue of waste disposal. Once you’ve used one of these pods, it’s usually far too easy to just chuck them into the bin, which isn’t an environmentally friendly way of disposing of them. Demonstrating the reusable capabilities of aluminium, Nespresso has teamed up with Swedish bike maker Vélosophy to create a bicycle made from recycled coffee capsules. The goal of the RE:CYCLE is to show what can be achieved by recycling the capsules and to promote reprocessing in general. ‘It is beautifully designed, responsibly sourced and sustainably produced,’ says Vélosophy founder and CEO Jimmy Östholm. The deep purple colour…

6 minuti
know your diamonds

THEY ARE up there with some of nature’s hardest and most thermally conductive materials, which means that diamonds are, literally, forever. The stones have been present throughout human existence and were said to have magical powers. Due to this, diamonds have carried an ascribed sense of value to what otherwise would be just another rock. In 1477, Archduke Maximilian I of Austria presented Mary of Burgundy with the first diamond engagement ring in the world. Fast forward hundreds of years, and diamonds helped to shape South Africa’s economy, politics, and culture. In the 1800s, De Beers dug a giant gaping hole in the ground in Kimberley to get to them, and became the ultimate global authority on the mineral’s sales, distribution and quality control. Today, diamonds have two kinds of value: Symbolic,…

2 minuti
patriot or traitor?

‘Arguing that you don’t care about the right to privacy because you have nothing to hide is no different than saying you don’t care about free speech because you have nothing to say…’– Edward Snowden IN 2013, at the age of 29, Edward Snowden shocked the world when he revealed that the American government was secretly embarking on a mission of mass surveillance against its own citizens. He exposed the underhanded tactics used by the American National Security Agency (NSA) who had been collecting every single email, phone call and text message without consent. His new book, Permanent Record, isn’t about the need to expose government secrets, but rather what it means to stand up for your own beliefs, and in Snowden’s case, what he believed to be unequivocally wrong. Is it…