Galileo helicopters

Aristotle believed that heavier objects would fall faster than lighter ones.
Galileo however, disagreed. He claimed that things would fall at the same time....but why are some objects, like a feather or a piece or paper different?
We have been discussing air resistance and investigating how long it takes for a 'helicopter' to fall.
Using small, medium and large paper cut out models we dropped them from a height and using stop watches, recorded our results.
Does the size of the rotor blades change the speed of a falling object?
Here are some of our results:

Galileo and the Pendulum

When Galileo was in church in Pisa he started watching the light hanging from the ceiling. It was swinging.

He was interested in how it was moving. Sometimes the wind would blow and it would swing more, then gradually it would slow down.

So he began experimenting with pendulums. He tried changing the size of the swing, the weight at the end of the string and the length of the string, and each time measured how long the swing took.

We used a timer to time ten swings of a pendulum.

We tried it with a big swing and with a little swing and found that the time the swings took was almost the same.

Galileo found the same thing and used the sameness of the pendulum swing to design a clock that would keep steady time: a pendulum clock. This was the beginning of pendulum clocks:

How the pendulum gives the tick tock of the clock

Galileo's design

The design built

Here it is, made out of cardboard by J. E. Johnson:

Pendulum clocks meant that people could measure time accurately at last. Before they could measure to the hour, now they could measure to the minute, the second even. Galileo's discovery changed the world.

Galileo's Journal

Today we read the book Galileo's Journal 1609-1610. It was all about the time when Galileo first pointed his telescope at the night sky.

We learnt about how he saw that Jupiter had moons that go round it!

Have a look at this video for more about that:

Discovering very big and (very small) things

When Galileo made his telescope,

He discovered things never seen before.

When Herschel made his huge, 12 metre long telescope, he discovered Uranus.


Have a look at this film, Powers of Ten, that shows some of the very big things that we then discovered: