Reflection Relay Robert C Fisler Elementary Science Olympiad Combined Grades Event March 16th, 2019

Rules A team of three students will be asked to bounce a light beam off each of their mirrors to hit a predetermined target 2 Parts for Local Competition 3 D activity where students will work together to bounce light onto a target Pencil and paper quiz where students will have to solve ray reflecting problems

Rules Continued Part 1 Hands On Three team members, each supplied with a pocket mirror, cooperate to bounce a light beam(from a flashlight, laser pointer, etc.) onto a predetermined target. The light must strike each of the three mirrors before hitting the target, and there may be obstacles that the beam of light will have to be directed around (see sample diagram). The three team members must cooperate to direct the beam of light on the target. They must use all three mirrors to change the light's path. Each team will be given up to one minute of preparation time before the clock is started.

Scoring When teams are ready or after their 1 minute prep time has elapsed the light source will be turned on and a timer started. Teams will attempt to hit the target as fast as possible. (light beam must remain on the target for 3 seconds to stop the timer) The objective will be to attain the lowest elapsed time in seconds. One point will be added for each second. No team will be allowed to use more than two minutes to accomplish the task. Maximum score will be 120 points. Just Like Golf Low Score wins

Part 2 While other teams are competing everyone else will be working on 6 Ray tracing problems(will discuss more in a minute) to determine which mirrors an imaginary light beam will hit. Each sheet is a different problem and all mirrors must be identified correctly in order to get credit for the worksheet. For each Sheet your team correctly completes 1 point (1 sec) will be deducted from your part 1 score.

What you need to Know? Light is an electromagnetic wave that travels in a straight line as long as it doesn’t run into anything When light hits a reflective surface such as a mirror it behaves in a predictable way. If the reflective surface/mirror is flat the angle of incidence will be equal to the angle of reflection All those big words but quite simply the angle that the ray comes into the mirror will be exactly the same as the angle it leaves the mirror

Visually this is what it looks like Angle X = Angle Y

Communication You will need someone to be the leader and take charge and tell the the others where to move and how to change the angle of their mirrors. If everyone is screaming and doing their own thing success is not likely Use your 1 minute preparation time wisely by putting yourselves into good positions to each other by using your knowledge of angles. Once timer starts have only person directing but all team members participating Person closest to light source needs to be the steadiest person because they will need to hold the mirror in the same position the longest

How to prepare for part 2 You will need a straight edge(ruler) and a protractor to measure the angles. Carefully use the ruler to draw a straight line from the source till it hits the first mirror (Record the letter of that mirror) Then use the protractor to measure the angle of incidence and mirror that angle to get the reflecting ray Draw a straight line until it hits the next mirror (record the letter of that mirror) Repeat steps until your ray goes off the paper Your Answer should be a list of Letters (ie A,F,H,Y) indicating the mirrors that the imaginary ray will hit.