7.4 Free fall Flashcards
What did Galileo Galileli find about objects falling
They must fall at the same rate, then any one such object must fall at the same rate as the rest put together. Any two objects must fall at the same rate regardless of their relative weights
How did Galileo Galileli demonstrate that objects fall at the same rate
He released two different weights from the top of the Leaning Tower of Pisa
Galileo and the inclined plane test
To find out if falling objects speed up as they fall
Rolled a ball down a plank, used a dripping water clock by counting the volume of the drips as a measure of time, measured how long the ball took to travel equal distances from rest.
What did Galileo observe and conclude from the inclined plane test
The ball was shown to have gained speed going down the slope and so concluded that an object falling vertically accelerates
How could we investigate the free fall of a ball
Make a multiflash photo or video of the fall from rest. Vertical metre ruler to provide a scale
Multiflash - ordinary camera with slow speed shutter, dark room illuminated with stroboscope
How can you tell if acceleration is constant from a set of results
Put it into suvat, s=1/2 at^2
Compare this with the general equation for a straight line y=mx+c
Let y represent s and let x represent t^2, m=1/2a and c=0
Then the gradient can be measured meaning the acceleration (2*gradient) can be calculated
As there are no external forces acting on the object apart from the force of gravity, this value of acceleration is known as the…
…acceleration of free fall
Represented by symbol g
Direction code for objects being thrown vertically upwards (suvat can also be used)
+ for upwards and - for downwards
