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Interestingly, however, the same doesn’t apply to sprinters. Because their races are shorter, they don’t breathe for so long, and because the air is thinner, so reducing aerodynamic drag, they can actually run faster at higher altitudes. This is why a number of world athletics records were set during the 1968 Mexico City Olympics (at an altitude of about 2,250 m/7,400 ft)51.

What’s so bad about cars? Driving a car is the next best thing to being a human cannonball. It can shoot you over the ground at a blistering speed for an amazing distance on a single tank of fuel. If your tank holds 70 litres (about 15 gallons), and your engine can manage 100 km (62 miles) on 7 litres (1½ gallons) of fuel, a single fill-up at the petrol station will power you a rather surprising 1,000 km (600 miles). So, stopping to refuel four times, you could just about drive across the United States from New York City to Los Angeles. That might sound impressive, but it’s nowhere near as good as it might be (or should be). If you want to get across the States, a car is probably a much better bet than the bicycles we considered in the last chapter – at least if you want to expend minimal effort and make the trip as quickly as possible without flying or taking the train. However, suppose you wanted to climb Mount Everest and such a thing were possible on foot, by bike and by car. Instantly, we find ourselves wondering ‘Do I really need to drag all that metal to the top?’ Carrying a bike would be bad enough, but if you drive a car up a hill, you’re lifting not just your own weight (something like 75 kg/165 lb), but the weight of the vehicle as well (which could easily be 1,500 kg/3,300 lb). This is the real drawback of driving a car. Wherever you go, it’s like having a ball and chain shackled to

Atoms under the Floorboard.indb 77

1/27/2015 8:39:50 PM

Atoms Under the Floorboards by Chris Woodford  

Seriously surprising science from the sofa!

Atoms Under the Floorboards by Chris Woodford  

Seriously surprising science from the sofa!