Catapult - Method, Tables and Graphs

How to draw a Table Label this using the ppt How to draw a Graph Label this using the ppt Why are these wrong? 2. Why should you try and have a big range of input variables? 3. Why is big scatter a bad thing? 4. What should you do if you’ve got a lot of scatter? i) ii)

Catapult Practical Name: The method and justification talks about how he made sure his experiment produced repeatable and accurate results. 1. What does repeatable mean? 2. a) Colour all the steps in the method which talk about repeatability ( b) Put a tick next to the ones which have been justified c) Choose one of the steps which isn’t justified and explain why it makes the results repeatable. 3. What does accurate mean? 4. a) Colour in one step in the method which talks about accuracy ( b) Why is step 8 not very ‘accurate’? c) Colour two points in the justification which talk about accuracy ( d) Put a cross next to one where he says that, in fact, he’s not being very accurate 5. Which stage in the justification talks about deciding the range? What is the range of input variable? What is the input variable in this experiment

Catapult Practical Name: The method and justification talks about how he made sure his experiment produced repeatable and accurate results. 1. What does repeatable mean? 2. a) Colour all the steps in the method which talk about repeatability ( b) Put a tick next to the ones which have been justified c) Choose one of the steps which isn’t justified and explain why it makes the results repeatable. 3. What does accurate mean? 4. a) Colour in one step in the method which talks about accuracy ( b) Why is step 8 not very ‘accurate’? c) Colour two points in the justification which talk about accuracy ( d) Put a cross next to one where he says that, in fact, he’s not being very accurate 5. Which stage in the justification talks about deciding the range? What is the range of input variable? What is the input variable in this experiment

1Catapult Practical2Distance travelled by the paperclipLHRubber band lengthBand 1Band 2Band 3(cm)24283236401014202629.79 - 1111 - 1718 - 2223 - 2928 - 3191122262811142023301017182931DHULVBHBVMHMVRHRVThe variable you controlled (input variable) goes in the first column(cm)Units go in the header not next to the valuesThe heading should describe what you are measuringNumbers should be in order, largest at the bottomThis is your estimate of the true value. More repeats  better estimate.This tells us how much scatter there is between repeats. Lots of scatter  hard to estimate true value.3Graph rulesInput variable (independant variable) along the bottom Numbers spread out evenly Label axes with units Sharp pencil (not crayon / felt tip) Crosses/points (not circles/shapes) GraphsPaperclip distance (cm)Rubber band length (cm)4ReliabilityIf you do the experiment once Results are not reliable (not repeatable) One outlier might change shape of curve You don’t know what the ‘true values’ are Paperclip distance (cm)Rubber band length (cm)Graphs5ReliabilityIf you do the experiment a few times You begin to see a pattern … lots of times… Too many points to draw