Electric Eels and Electric Fish
Did you know that fish like the electric eel and the electric ray can produce high voltage electric shocks as high as 700 volts. Although these electric shocks can only be discharged in short bursts they are extremely effective as both an attack and defense mechanism. To put things into perspective the electricity levels involved with an eel could protect it from most large predators such as anacondas and crocodiles, and may even be enough to kill a human.
So how on earth do they create electricity from within their own bodies. The answer lies in the presence of specialised cells called electrocytes. On average an electric eel might have around 7000 of these cells and with each cell being able to produce 0.1 volts of electricity you can quickly see where all that voltage comes from.
The Kangaroo Hop
Did you know that the kangaroo is the only large animal that uses hopping as a form of movement. In fact the kangaroo hops so efficiently that it can easily hop at speeds of around 25mph for distances up to 2km and over short distances can hit speeds as high as 40-45mph.
Despite the kangaroo having such a fast and energy efficient hopping technique it unfortunately cannot walk in the conventional sense. Rather it uses its tail and fore limbs to help it pivot and almost crawl if it needs only move a few steps.
Water Can Crack Metal
Did you know that water can expand in volume by around 1/9th of its total composition. This means that when frozen it occupies more space than when in liquid form.
The above phenomena is very common in houses where water pipes burst over the winter due to ice forming in the pipes. The pipes which were once wide enough for water to go through are now too small when the ice forms.
The brittle nature of the metal when it feezes combined with the ice expanding causes them to crack. In fact the enormous power of frozen water is also used in quarries to loosen up huge blocks of rocks.
What Is a Light Year?
A light year is the total distance travelled by a beam of light in one year. A beam of light can travel at up to 300,000 km/sec and the approximate distance covered in a year works out to be 9,470,000,000,000 km (1 light year = 9.47 x1012 km). So why did scientists create this new unit of measure ?
Well as you can imagine the universe is so vast that talking about the distances between stars and planets was just unmanagable with miles and kilometres. For this reason a standardised unit of measure which we call the light year was created.