Pedagogy in Action > Library > Using Direct Measurement Videos to Teach Physics > Video Library > 2-Dimensional Motion

# 2-Dimensional Motion

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.

#### Low-friction puck slides across lab floor

Screen shot from a video of hover puck on lab floor (Quicktime Video 2MB Jul7 12)
This clip shows a low-friction puck sliding across a lab floor. The camera is mounted on the ceiling. A grid allows students to measure x-direction and y-direction motion separately. The puck moves with constant velocity, allowing students to develop skills for motion in two dimensions, without the added complexity of acceleration.

Video file: video of hover puck on lab floor (Quicktime Video 2MB Jul7 12)

Sample question 1: Determine the x-axis velocity.

Sample question 2: Determine the y-axis velocity.

Sample question 3: Use vector addition to find the direction the puck travels and compare this value to the angle when the puck passes over the protractor.

#### Bounced Tennis Ball

Shows a ball bounced across a stage floor.

Here are QuickTime files:

original file: video clip of tennis ball bounced across stage (Quicktime Video 2MB Jun5 12)

New file Oct 2013: Ball bouncing across a stage (Quicktime Video 4MB Oct24 13)

Note: ball moves from right to left, and measured quantities are different from the Youtube video at right

Sample question: Determine the direction the ball is traveling just as it leaves the floor when it bounces on the left side of the stage.