Albert Einstein/ The theory of relativity
Written in 6th grade
Who was Albert Einstein?
He was born in 1879 in Ulm in Germany, and died in 1955 in Princeton in the USA. He was a scientist who became famous for the “Theory of relativity”, which he discovered in the beginning of the 1900s. He is often called “The father of the modern physics”. In 1921 he got the Nobel Prize in physics.
Einstein’s basic principles:
- The laws of physics are the same regardless of how fast you are travelling.
- Speed of light is the same regardless of how fast you are travelling.
- Nothing can travel faster than the light.
Einstein’s well-known equation
The mass is a form of energy and can be transformed into kinetic energy for example in nuclear power stations and nuclear weapons (for example heat energy is kinetic energy).
What is a theory of relativity?
Mass, length, speed and time are not absolute but they differ in relation to the observer.
Example 1:
I drive a car at 100 km/h and shoot a pistol shot with a speed of 1500 km/h in the direction of movement. A person who is standing still, looks at it and sees the bullet travel in 1600 km/h
The speed of the car relation the ground is 100 km/h
The speed of the bullet in relation to the car is 1500 km/h
The speed of the bullet relation of the ground is 1600 km/h
Example 2:
I walk on an escalator in 3 km/h at an airport, and the escalator moves in 2 km/h. My friend stands beside the escalator and sees that I have a speed of 5 km/h.
My speed in relation to the escalator is 3 km/h
The speed of the escalator in relation to the ground is 2 km/h
My speed on the escalator in relation to the ground in
5 km /h
Example 3:
I stand still on Earth. But if a marzipan observes me from the Mars, the Earth is moving around the Sun at 100 000 km/h.
Furthermore, when somebody in a spaceship in another Galaxy is observing my solar-system moving in my Galaxy, Milky Way, I am moving at the speed of 792 000 km/h.
Conclusion
Everything is relative; it depends on who or from where somebody observes something.
Before Einstein came up with his theory people believed that speed, time and length were absolute.
Photo links: http://www.asperger-historia.se/einstein.jpg , http://en.wikipedia.org/wiki/Albert_Einstein , http://3.bp.blogspot.com/_LWjEK8-NrgQ/ShPxnIkdMoI/AAAAAAAAAV8/7Mc78sI74Ig/s400/050405_einstein_tongue.widec.jpg.jpeg
Info links: http://en.wikipedia.org/wiki/Albert_Einstein , www.isv.uu.se/thep/talks/rikard/oppethus09.pdf , www.robotbyn.se/astrofysik/relativitetsteorin.php