Question 3: Did you know a physical experiment at school which particularly impressed you? What are the physical experiments which impress you?

Reinhard Scherm, former PTB Department "Fundamentals of Physics and Metrology": As a schoolboy, I hung around at the German Museum in Munich for one week every year. They had a cloud chamber there!!

Annette Paul, PTB Working Group "Environmental radioactivity": After a lesson on induction, I bent a wire to form a coil, fed it with current via a battery and then brought it close to a compass. Induction! (7th grade)

Albert Einstein (1897 - 1955): “As a child of 4 or 5, it was a miraculous experience for me when my father showed me a compass [...]. There had to be something behind things which was not yet known.”

Andreas Bauch, PTB Working Group "Unit of time": We had an air-cushion path for experiments on linear momentum / elastic and inelastic impact etc. We also let spheres, hollow spheres, cylinders etc. roll on inclined planes and determined the ultimate velocities. We were allowed to lay out and evaluate the experiments ourselves. And in most cases our results agreed with those of the textbook!!

Niels Bohr (1885 - 1962): “In Manchester I carried out a theoretical investigation into the velocity loss atomic particles suffer when passing through matter. Most of all I was fascinated with the prospects opened up by the discovery of the nucleus for further information about the characteristics and relations of the elements; this could obviously be realized only by fundamental departures from the aspects of classical physics so complete and fruitful in many fields.”

Marie Curie (1867 - 1934): From her early childhood, Marie Curie was particularly fascinated with the physical equipment in the study of her father, who was a grammar school teacher.

Gesine Grosche, PTB Working Group "Unit of Length": Coupled pendula.

Ernst O. Göbel, President of the PTB: Yes, the Franck-Hertz experiment!

Hermann von Helmholtz (1821 - 1894): While his classmates were reading Cicero or Vergil, Helmholtz calculated under his school desk the radiation path through telescopes.

Uwe Keyser, former PTB Department "Focal Points of Experimental Research": Tesla transformer; detection of gravitation waves