|
A disc-shaped stone has to be tossed at an angle of 20 degrees to achieve the maximum number of bounces across water. 将碟状石子以20°的角度投出可以打出最多次数的水漂。 Inspired by English scientist Barnes Wallis, who invented the bouncing bomb, researchers have described the complicated physics behind the water-skipping behaviour in stones, toys and even cannonballs. 英国科学家巴恩斯·威利斯发明了弹跳炸弹，受其启发，研究人员解释了石子、玩具甚至炮弹在水面弹跳这一现象背后的复杂物理原理。 Naval gunners as far back as the 18th century bounced cannonballs as a military tactic. 上溯到18世纪，海军炮手将炮弹弹跳作为一种军事战术。 'Designed to breach German dams, the weapon skipped over the water surface to avoid undersea torpedo nets.' “为了破坏德国大坝，炸弹在水面上弹跳以避开水下鱼雷网。” Writing in Physics Today, they say water skipping has returned to more docile roots of late with toy balls that make it much easier to achieve multiple hops. 《今日物理》写到，如今，随着玩具球的出现，打水漂已经变得更加容易驾驭，多次弹跳也变得简单了许多。 The researchers said: 'Those spheres are made of an elastic material whose high compliance - or ability to readily deform - introduces some interesting changes to the skipping phenomenon.' | 
