1. Bell ringer: Day 2 Finish debrief from yesterday

2. What is a Pendulum? A pendulum is a point of mass called a “bob” hanging from a length of string or rod. A simple design that revolutionized science bob Point of equilibrium Pivot point

3. A-oh...my name is Galileo! Born in Italy, in 1564 Sitting in church one day Galileo noted that chandelier swinging in a breeze kept the same frequency of swing whether it was swinging out in a wide or narrow arc. Galileo thought that this might work well to make more accurate clocks. A year later he died in 1642

4. Timing is everything! Before the pendulum, people didn’t have a reliable way of keeping accurate time! Scientists couldn’t measure the timing of something with precision. Allowed time to truly take its place as a fundamental quantity.

5. Words to know… Cycle- One complete swing from left to right or right to left. Frequency- Number of Cycles in a measure of time. Amplitude- How far back you pull the “bob” back. Period- The amount of time it takes the bob to make 1 cycle

6. Welcome to the LAB In your groups designate one person as the : –holder/dropper –data recorder/counter –Timer Your task is to find the best way to get the most consistent data set with your pendulum. –We will consider 3 trails with the same data as consistent data. Record: –Angle of amplitude –Mass of bob (mass of 1 washer 28.4g) –Length of rod –Frequency –Duration of time used to find frequency

7. Day 2 Pendulum Lab

8. Let’s Test it Out! Question: What variables might affect the frequency of a pendulum? We can test how length of rod and mass of bob affect the pendulum’s frequency. –Length and mass are our independent variables What are our constants (things that don’t change) ? –Amplitude –Time (ex: count for 60 sec each time)

9. Hypothesis Your going to need to record your hypothesis. This should be written as an, “if/than/because” statement. Ex: If I _________, than __________ will happen because_____________.

10. Nothing but the data Data should be recorded in either a chart or a table. –Remember to title it –Record measurements and units