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Very good.
I couldn't find your summary related to the cooperative learning activity; what a pity!

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The  simultaineity is the phenomeno when two events happen at the same moment. The simultaneity of two events is not absolute,but depends on the reference frame,so it is a relative system.

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The experiment of Michelson and Morley (STEP 3)

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The experiment of Michelson and Morley (STEP 3)

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Maxwell tried to solve the contraddition:
can be assumed that the Galilean’s law are valid in a reference frame where the luminous aether is at rest.
So the speed of light light could be calculated only in that system.
A Michelson and E Morley carried out an experiment in order to scoop the  “aether wind”, so the motion of the Earth through the aether and to confirm the plausibility of Maxwell’s hypothesis.

A beam of monochromatic light is divided by a beam splitter . The divided beams reach two mirrors, are returned and recombined by respectively transmission and reflection at the beam splitter.
a beam of light (actually continuous) is split when it strikes a transparent plate: part is transmitted, part is reflected. When the two divided beams return to the block, partial reflection and partial transmission also combines them.
Following Galilean/Newtonian Physics, let us suppose that light travels (at c) with respect to a 'stationary' medium (called the æther). For our purposes, suppose that it be set up with l1 = l2 and that the whole spectrometer be stationary with respect to the æther, the medium that supports the wave motion of light. Let's consider a point in the interference pattern at which the phase difference is zero.  The transit times are no longer equal, but for the horizontal and near vertical directions are given by:
t1= l/ √(c^2-v^2) + l/√(c^2-v^2) = 2l/c√(1-v^2/c^2)
t2= l/(c+v) +l/(c-v) = 2l/c(1-v^2/c^2)
By rotating the spectrometer 90 degrees, one can compare the effect of speed through the putative æther on one of the beams. Then by making measurements six months apart, one can add or subtract the speed of the Earth through the æther. The speed of the Earth in its orbit around the sun is v = 30 km/s. Substituting in the equations above (and using l = 11 m - for an optical spectrometer, it was a seriously large!) the phase difference expected would be Δφ = 2πΔt(c/λ) = 2.3 radians = 0.4 fringes.
The conclusion was that the aether didn't exist and the failed of experiment was a big opportunity to introduce the relativity of Einstein

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Bene; continua il tuo padlet!

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2A: Work on the vocabulary: match each word with the definition (you have 10 min), then (as homework) write all sentences in your learning diary.
-Dilatation is the act of expanding
- Contraction is the act of contracting
-Reference Frame is a set of coordinate axes in terms of wich position or movement may be specified
- Inertial Frame is a reference system in wich the Newton's first law is valid
-Galilean Trasformation of coordinates is the relation betweenthe coordinates of an event as observed from two inertial reference frames
-Medium an intervening substance throughwich something is transmitted or carried on ether is an all pervading infinitely elastic massless medium
-Vacuum is absence of matter
-Simultaneity is happening at the same time
-Elementary Particle is any of the subatomic particle that compose matter and energy Rest Frame is the coordinate system in which the particle is at rest
-Stationary is a time-invariant quantity, such as constant position or temperature

2B :

https://www.youtube.com/watch?v=ttZCKAMpcAo
1) The Newtonian dynamics appeared to have definitively solved The question of describing motion and its causes
2) In classical mechanics speed is not absolute but always relative To a reference frame
3) If a law of mechanics is valid in a reference frame K, it must be valid in all reference frames K’
moving With uniform linear motion in relation to k.
4) Galileian law for the addition of velocities is also valid.
5) Maxwell developed the theory of electromagnetism around
1870.
6) In electromagnetism the speed of light in a vacuum is  Constant
7) This is the fundamental postulate of Special Relativity , called Invariance of the speed of light.

2D: Running dictation.
The correct phrase is:
"The Michelson-Morley Experiment Peraphs a privileged reference frame exists, it was called by Aristotele “ether” and the M-M experiment had the aim to demonstrate the ether existence."

2E
https://www.youtube.com/watch?v=7qJoRNseyLQ
Question: What Was the Michelson-Morley Experiment?

Answer: The Michelson-Morley experiment was an attempt to measure the motion of the Earth through the luminous ether Though often called the Michelson-Morley experiment, the phrase actually refers to a series of experiments carried out by Albert Michelson in 1881 and then again (with better equipment) at Case Western University in 1887 along with chemist Edward Morley. Although the ultimate result was negative, the experiment key is that it opened the door for an alternative explanation for the strange wave-like behaviour of light.

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1 B:
1) What happens to the plexiglass sheet (targa) after the bump ?
It flies away far from the tube.
2) What happens to the disk of wood ?
It falls down inside the tube.
1 C:
When the position of a body with respect to its surroudings doesn't change with time it is said to be " AT REST ", while if the position of an object is changing, it's " IN MOTION ".
1 D:
Peter-  Have you seen Mark ? The small sheet of plexiglass jumped away, but the disk of wood fell into the tube.
Mark- Yes i saw ! So the disk of wood was AT REST and finally it is still AT REST, even if in a different position.
Peter-  You are right, Mark! Instead the sheet of plexiglass was AT REST but at the end it is IN MOTION.
Mark- Imagine to be seated on the plexiglass palet, what would you do after the bump ?
Peter- I'm sure i'd be AT REST ! But, if i where stuck on it i'd go away with it.
Mark- In this case with respect to the layer you would be AT REST but with respect to the surroundings you would be IN MOTION, wouldn't you ?
Peter- Yes , it's correct! ! Teacher, what changes the stationary state of an object ?
Mark-  or its speed, if it is already IN MOTION ?
Teacher- I ivite you to watch another video, then we can discuss it.
http://www.youtube.com/watch?v=0oyJmFe3ffg

At the beginning in the  system the forces are balanced, because force of gravity is opposed to normal force pushes upward. In a second moment when we hit the card with extreme force, the coin doesn't move because follow the Law of Inertia ; so the coin falls into the glass.
To show the force of inertia in the second part of the video there is a caterpillar into an apple. We hit the apple and it will move with a certain speed, which is equal for both. After we stop the apple but the caterpillar instead continue to move depending on the force of inertia.

1E:
An object will continue to remain at rest unless acted upon by an external unbalanced force. This is the first law of dynamics; it was understood by Galileo Galilei that described it in 1632 and then it was enunciated by Newton in 1687. The law also states that an object will stay in a state of constant velocity, called uniform motion, in the absence of an unbalanced force. It means if there was no frictional or any other force the body would never stop.

1F:
A,B,C,D are four people. “A” is stationary in a bus and the bus is moving. Draw A, B, C and D inside or outside the bus so that B is stationary but in motion with respect to A, C is in motion with respect to B, D is in motion with respect to C but stationary with respect to B.
A INSIDE
B OUTSIDE
C INSIDE
D OUTSIDE