Slide Your Mass Over Learning and Applying the Skill of Using the Triple Beam Balance
Section A – Skill Acuisition General Introduction to Skill A balance is generally used for weighing out small amounts of chemicals to use in solutions and determining the mass of different objects in physics in grams. Learning how to use a balance is important for collecting data or information and for ensuring accurate mass measurements.
Curriculum Objectives S2-0-5 -5aa Sele Select ct and and use use appr approp opri riat atee met metho hods ds and and tool toolss for for coll collec ecti ting ng data data • S2-0 or information. S2-0-5 -5b b Esti Es tima mate te and and meas measur uree accu accura rate tely ly usin using g Sys Syste teme me nte ntern rnat atio iona nall • S2-0 !S" and other standard units. nclude# S con$ersions.
alance pan Adjustment screw
iders ↓
eams ↓
+ointer ↓ Scale
Special Safety, Care, and Handling Aspects • %a&e sure the riders are at 'ero before carrying the balance. • (arry the balance with both hands and &eep it hori'ontal. • )o not place anything hot directly on the balance pan. chemicals directly on the balance balance pan. • *e$er pour chemicals • +lace balance on a le$el, sturdy surface and away from hea$y traffic. traffic.
Setting Up te !alance • %a&e sure the riders are at 'ero. • (hec& to ma&e sure the pointer swings freely along the scale. • /se the adjustment screw to obtain an eual swing of the beams, if necessary.
"e #rocedure $it an Analogy Loo& at the riders on your balance. 1hese will be used for balancing the weight of an object on the balancing pan. ne is 300 grams, one is 30 grams and one is 3 gram. 1hin& of it this way# if you wor&ed at a ban& with only 4300 bills, 430 bills, loonies, and small change and you ha$e to gi$e somebody 456.50, they would probably appreciate it if you ga$e them the fewest amounts of bills possible. 7ow would you do this8 9ou would start by gi$ing them si: 4300 bills, then fi$e 430 bills, then three loonies and small change last. ;hen using a balance, you do not &now in ad$ance how many grams an object weighs, but you will
. 1o find out the total mass of the object, you simply need to add up the three amounts indicated by the riders. ?or e:ample, if an object balanced with the 300 gram rider in the third notch from 'ero, the 30 gram rider in the fifth notch from 'ero, and the 3 gram slider at 6.5, the total mass of the object would be !300 grams : 6" @ !30 grams : 5" @ 6.5 grams 656.5 grams.
Skill %evelopment 3. 7a$e each student in your group pic& an object from your possessions to weigh. List the objects chosen and your estimation of their masses in the table. Object
&stimated 'ass
Actual 'ass
2. 7a$e each person determine the weight of their object using the balance and fill in the actual mass column of the pre$ious table. 6. Explain your procedure for finding the mass of your object. nclude all calculations. 9ou may use drawings to assist your e:planation.
Section B – Skill Application !ackground Information %omentum is the product of mass and $elocity. %omentum is also conser$ed. 1his demonstration and following in$estigation is designed to e:plore the two factors of momentum in more detail for the purpose of deepening understanding and de$eloping inuiry and in$estigation s&ills.
Curriculum Objective S2-6-0B )efine momentum and impulse and ualitati$ely relate • impulse to change in momentum for e$eryday situations.
'aterials • %easuring tape • %etre stic& • Scale • (hair • as&etball • +ing-pong ball and fussball about the same si'e • alls of a $ariety of masses !eg. baseball, tennis ball, golf ball, floor hoc&ey ball"
Safety Suggestions • A
Introduction Activity Cet into groups of > or 5. +erform the acti$ity and discuss and record your answers to the following uestions as a group. 3. egin by holding a metre stic& upright from the floor. 7old a bas&etball so that the bottom of it is at e:actly one metre beside the metre stic&. Predict how high the bas&etball will bounce when released. Observe what the
height of the lowest point of the ball is at the highest point of the bounce after the ball is released. 2. epeat this process for a ping pong ball. 6. +lace the ping pong ball on the top of the bas&etball and predict what will happen when this is released at one metre. Explain your reasoning for your predictions. +rediction# DDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDD E:planation# DDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDD DDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDD DDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDD >. )rop the bas&etball with the ping pong ball resting on top !you may ha$e to hold it there with a finger on top" and observe what happens a few times. 1ry to explain it if it was different than your prediction. E:planation# DDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDD DDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDD DDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDD n this acti$ity you obser$ed that when a big ball with a small one on top of it is released from a one metre height, the big ball remains stationary on the floor and the small ball goes flying. 1his is because of the momentum of the object. The momentum of an object is affected by its mass and its velocity . 1his is why when a large mo$ing object !the two balls together" brea&s apart into a smaller mo$ing object !the small ball" and a stationary object !the bas&etball", this smaller mo$ing mass ta&es all the momentum of the original object and results in a much larger $elocity.
In(uiry 3. ;hat variables from the demonstration could you manipulate to learn more about momentum !list at least three"8 DDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDD DDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDD 2. Suggest at least three inquiry questions you could in$estigate based on uestion 3. DDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDD DDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDD
DDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDD DDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDD Some inuiry uestions to consider are# a. )oes the mass of the top ball affect the height of the bounce8 b. )oes the mass of the bottom ball affect the height of the bounce8 (hoose one of the suggested uestions for in$estigation ! a or b from abo$e". 6. ;hich uestion ha$e you chosen to in$estigate8 DDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDD >. ;hat is the $ariable you will manipulate8 DDDDDDDDDDDDDDDDDDDDDDDDDDDDDD 5. ;hat $ariables will remain the same8 DDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDD DDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDD . ;hat is the effect you are measuring !what is the result of manipulating the $ariable from >"8 DDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDD F. a. ;hat will you use to measure the $ariable you will change8 DDDDDDDDDDDDDD b. ;hat units will you use to measure this $ariable8 DDDDDDDDDDDDDDDDDDDDDD B. a. ;hat will you use to measure the result8 DDDDDDDDDDDDDDDDDDDDDDDDDDDDD b. ;hat units will you use to measure the result8 DDDDDDDDDDDDDDDDDDDDDDDDD G. List the materials you will need. DDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDD DDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDD 30.List any safety precautions you must ta&e while conducting this in$estigation. DDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDD DDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDD DDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDD Cather the materials listed in G.
#rocedure List the steps of your procedure, ma&ing sure to perform multiple trials of each demonstration to ensure accuracy. 9ou may also use pictures or diagrams to clarify steps. 9ou are pro$ided with and are e:pected to ma&e use of the table and graph paper pro$ided.
Observations "rial )
Conclusions 33.E:plain the outcome of your inuiry, based on the table and graph you ha$e made. DDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDD DDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDD DDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDD DDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDD 32.%omentum is the product of mass and $elocity. 7ow does this in$estigation support this statement8 DDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDD DDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDD DDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDD DDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDD 36.;hat is another uestion you would li&e to in$estigate8 DDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDD 3>.;hat is your prediction of the results8 DDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDD DDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDD DDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDD DDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDD
*eferences • http#HHwww.hometrainingtools.comHarticlesHhow-to-use-triple-beam-balanceteaching-tip.html • http#HHideaplace.orgH(hemistryH(hemLabsHalance.html • http#HHwww.physics.smu.eduHIscaliseHapparatusHtriplebeamH • http#HHwww.newton.dep.anl.go$Has&asciHgenGGHgenGG35>.htm • http#HHfindarticles.comHpHarticlesHmiDg:522HisD2002HaiDn3G3>6F>B • http#HHwww.glenbroo&.&32.il.usHgbssciHphysH(lassHmomentumHmomtoc.html
