Tuesday, Sept 16, 2008 - Block 1

Collect Sun Lab

Hand back RA 1

Showed Cosmos clip

Go over RA 1
Go over Sun Lab Model showing linear sun, why image is inverted, and why you can get the image of the Sun regardless of the shape of the hole.

Quiz on uncertainties tomorrow - also need to know formulas for circumference, area, volume.

Intro to Linear Motion
Views of Aristotle

Genius of Galileo was to image a world in which he could remove contact friction and air resistance.

Thought experiment of rolling balls showing idea of inertia.
Thought experiments showing that two objects should fall at the same rate if there is no air resistance.
Galileo dealt with rates - how some quantity changes with time.

distance - how far you travel
speed = distance/time (rate at which you cover distance)
average speed = total distance/total time
instantaneous speed = how fast at any instant in time

displacement: How far from some starting point and in which direction
velocity: how fast and in what direction
average velocity = change in displacement/total time
instantaneous velocity = how fast and in which direction at an instant in time

Handed out RA 2.1 due tomorrow.