Interleave the pages of two thick phone books one by one, then pull: the tension presses the sheets slightly against each other, which multiplies the friction. Hundreds of small forces add up. In a televised demonstration, it took two armoured vehicles to pull them apart, and physicists published the full explanation in 2016.
Cooled below −183 °C, oxygen turns into a pale blue liquid. Pour it between the poles of a strong magnet and, instead of flowing away, it hangs suspended between them. The reason lies in its unpaired electrons, which respond to the magnetic field. Liquid nitrogen, by contrast, is colourless and pours straight through.
In 2012, Felix Baumgartner jumped from a capsule hanging beneath a balloon, about 39 kilometres up. In that extremely thin air almost nothing slowed him down, and he reached around 1,358 km/h in free fall, or Mach 1.25. He became the first person to exceed the speed of sound with nothing but his own body.