# Energy

Videos shown here contain grids, rulers, frame counters and other overlays that allow students to make measurements directly from the videos. Students can use this data to answer questions and solve problems. For each video, sample questions are shown, and in some cases, sample lesson plan ideas.
To analyze a video frame-by-frame, you will want to download the video file to your computer and open it using QuickTime. Clicking on the links shown here will allow you to view the video in your browser, but you may not be able to view the video frame-by-frame.

#### Spring-Shot Cart

This clip shows a small cart launched by a spring.

Download the QuickTime files: Direct Measurement Video of Energy in a Cart and Spring (Quicktime Video 5.5MB Jan25 14)

Sample question: Is energy conserved as the cart is launched?

#### A Pendulum

This clip shows a pendulum swinging. You can measure quantities to calculate the mechanical energy at various locations.

Download the QuickTime files: Direct Measurement Video of Energy in a Pendulum (Quicktime Video 6.4MB Jan25 14)

Sample question: Is energy conserved as the pendulum swings?

#### Puck Slides on Smooth Surface

This clip shows a small puck sliding along a smooth surface.

Download the QuickTime files: Direct Measurement Video of a puck sliding (slow) (Quicktime Video 7.1MB Jul15 13) here and Direct Measurement Video of a puck sliding (fast) (Quicktime Video 6.3MB Nov8 13)

Sample question: What is the relationship between the speed of the cart and the distance the puck slides?

#### Dry Ice Puck Slides on a Circular Hoop

This clip shows a small puck made of dry ice sliding along a circular hoop. The disk slides along the surface of the hoop, but loses contact with the surface as it speeds up.

Download the QuickTime file: Direct Measurement Video of a dry ice puck sliding on a circular hoop (Quicktime Video 9.6MB Mar26 13) here.

Sample question: At what angle should the puck leave the surface if it is frictionless? At what horizontal location would a frictionless puck cross the ruler at the bottom of the screen?

#### Gravity-Powered Clock

This clip shows a time-lapse video of a "grandfather clock". The video shows the rate at which the suspended weights move downward over several days of operation. Note that students can make reasonably precise measurements from this YouTube video without needing the QuickTime version.

Sample question: What is the power used by the clock?

#### Cart Rolls Down a Ramp and Collides with Spring

Screen shot from a video of a cart rolling down a ramp into spring (Quicktime Video 2.9MB Jul7 12)
This clip shows a low friction cart rolling down a ramp and colliding with a spring at the bottom of the ramp. The video is filmed with two separate cameras, so you can see how far the spring is compressed when the cart reaches the low-point of its motion.

Download the QuickTime file: video of a cart rolling down a ramp into spring (Quicktime Video 2.9MB Jul7 12) here.

Sample question: What is the force constant for the spring?

#### Roller Coaster 1

This clip shows roller coaster recorded using a high-resolution high-speed camera. The roller coaster has just rolled down a hill 60 meters high.

Download the QuickTime file: Video of roller coaster 1 (Quicktime Video 11.2MB Jul23 12) here.

Sample question: What is the velocity of the roller coaster?

Sample question: Was mechanical energy conserved?

#### Ballistic Pendulum

Screen shot from a Video of M&M candy ballistic pendulum (Quicktime Video 1.3MB Jul7 12)
This clip shows a M&M candy fired from a pneumatic cannon into a cup that is free to swing as a pendulum.

Download the QuickTime file: Video of M&M candy ballistic pendulum (Quicktime Video 1.3MB Jul7 12) here.

Sample question: Determine the velocity of the bullet as it leaves the pneumatic cannon.

Sample activity: Analyzing a Direct Measurement Video of a Ballistic Pendulum

#### Trampoline jumping

Screen shot from a video of person jumping on a trampoline (Quicktime Video 7.7MB Jul9 12)
This clip shows a person jumping on a trampoline.

Download the QuickTime file: video of person jumping on a trampoline (Quicktime Video 7.7MB Jul9 12) here.

Sample question: Determine the ratio of elastic potential energy when the jumper is at the low point to the gravitational potential energy when she is at the high point. Also, explain why you do not need to know the mass of the jumper to answer this question.

Sample activity: Direct Measurement Video of a Girl on a Trampoline