Presentation on theme: "CeAnn Chalker Patrick Chalker"— Presentation transcript:
CeAnn Chalker Patrick Chalker
Students will make: Metric Estimations then Metric Measurements on identical objects
* Mass * Volume * Density * Area * Force * Distance * Time * Temperature
* Students rotate between stations for each of the two parts of the event * Supervisors furnish all pencils, paper, and measuring devices * Teams may bring non-programmable calculators for the Measurement Part only. * Property to be estimated/measured and Units of Measurement will be given at each station.
* Approximately 30 seconds for each station * All answer recorded on form provided by Event Supervisor * Answer form MUST be turned in before Measurement Part begins * Students may not use any kind of measuring device (fingers, pencils, clothing, paper, etc.)
* Students may not Touch or Feel any objects unless specified in directions * NEW!!! Students MUST be allowed to “heft” an object if the mass is to be estimated.
* Approximately 60 seconds per station * All answers recorded on new form provided by Event Supervisor * Measurements are made using the instruments supplied at each station * All objects will be measured by the Event Supervisor prior to the competition using the same instruments the students will use
* To receive points, 3 requirements * Proper Resolution * Estimated digit Appropriate for the Instrument * Proper Unit of Measurement Ex. – Answer should be grams or g on a standard Triple Beam balance Wrong answers would include – 17.2 grams, 17.2 g, or 17.25
* Direct Measurements - not involving calculations, readings directly from an instrument (e.g. length, volume, mass, etc.) * Calculated Measurements - measurements that require mathematical calculation to achieve (e.g. calculating the density of an object, height using triangulation, surface area, velocity, etc.).
* Students record measurement to +/- 3 of the estimated digit of the instrument’s resolution. * Direct Unit Conversions are considered Direct Measurements.
* The smallest actual graduation or markings on the instrument
* A rock has a mass of 56.54g. Using a triple beam balance to find that mass. * A line on the floor is cm. Using a meter stick to measure the line a student adds 100cm to cm to come up with cm
Ruler has the smallest resolution of 1 mm * Width of object #1 - Measurement of mm * Answers between 209.0mm mm would be correct Triple Beam Balance has smallest resolution of 1/10 th of a gram * Mass of rock – Mass of grams * Answer grams – grams would be correct
* Students take direct measurements and make mathematical calculations obtain the correct answer. * More difficult to obtain exact answer * Various points are awarded for answers within.5%, 1%, and 2% of the correct value.
Surface Area * A rectangular box with dimensions cm x 4.63 cm x 4.63 cm. To calculate the surface area 2(4.63x4.63) + 2(4.63x10.62) + 2(10.62x4.63) = = cm 2 * A circle with the diameter of 9cm, the area of that circle is x = cm 2
* Both parts (Estimation and Measurement) are rated on accuracy * Rankings are the highest combined score * Three separate methods of scoring are used
Points based upon the percentage of the correct value for each station * 5 pts – Answers within 5% * 3 pts – Answers within 10% * 1 pt – Answers within 20%
* 5 pts – Answer expressed to the instrument's resolution +/-3 of the estimated digit * 0 Pts – All other Answers
Points based upon the percentage of the correct calculated value for each station * 5 pts – Answers within 0.5% * 3 pts – Answers within 1.0% * 1 pt – Answers within 2.0% * 0 pts – All other answers
* Break everything down to the fundamentals * Useful Formulas * Finding new things to measure * Conversions and units
* Comparing size and mass to known objects * Estimating time by average * Crazy (but measureable) stations
* Measuring irregularly shaped objects * Massing something on an open hand * Using a triple beam balance under time constraint * Items that seem easy but are very difficult * Approaching measurements in the same way EVERY TIME
* Practicing measuring with time * Coaching confidence (and a bit or arrogance) * Teamwork, dividing the workload * Mental math
* Put school name and team # on EVERYTHING! * Put labels for units on EVERYTHING! * Look at the measuring tool first, and then the object to measure second. * Check to see if measuring devices are zeroed or in need of zero-ing.
This is just a sampling of formulas students should know, there are many more to learn. * F=ma, Force = mass x acceleration * A=∆V/∆T (Acceleration = change in Velocity divided by Change in time) * A=(V 2 -V 1 )/(T 2 -T 1 )
* SA = πr 2 + πrl (surface area of a cone) * SA = 2ab + 2bc + 2ac (surface area of a rectangular prism) * Surface Area of a Sphere = 4 pi r 2 * Surface Area of a Cylinder = 2 pi r pi r h * g=-9.81 m/s 2 (Earth’s gravitational constant) * 1 N = 1 kg (m/s 2 )