What is length contraction? Easily explained

An important part of the theory of relativity is length contraction. In this post we explain what that means exactly.

Length contraction - what is it?

As you can read in our article on the subject of "time dilation", the properties of objects behave strangely when they move with the speed of light.

• The whole thing is also the case with the length of objects. In this example we are on a planet that does not move relative to us. In this case, the speed (V) is 0. Let us now assume that you are looking up at the sky and see a spaceship with an approximate speed of light (V = 0.99 ⋅ c) flying by.
• You would now find that the spaceship is shorter. However, if you would measure the spaceship with a measuring tape, you would get the same length as with a stationary spaceship. The tape measure also shrinks.
• The length of a body is therefore relative in its direction of movement, the body having the greatest length in the rest position. However, no contraction occurs perpendicular to the direction of movement.
• The relative length can also be calculated. The formula »l = l '⋅ √ (1 - V²: c²)« is used for this.

In the next practical tip, we will explain what alpha and beta radiation is.