William Carey Christian School
Advice of Year 11 (Preliminary) Assessment Task
Subject/Course: Physics
Description of assessment: Practical Exam Your assessment task will involve the following aspects: o Describing the demonstrated motion of an object o Identify energy transformations involved o Use supplied information to analyse the forces involved in a system of moving objects o Follow a supplied method to investigate the motion of an object experiencing a net force o Reporting in appropriate forms about the investigations you have carried out o Drawing and justifying conclusions from gathered data
Date of task: 16th and 17th August 2007
Weighting of assessment (%): 25
Outcomes Assessed:
P2 applies the processes that are used to test and validate models, theories and laws of science with particular emphasis on first-hand investigations in physics P6 describes the forces acting on an object which cause changes in its motion P7 describes the effect of energy transfers and transformations P11 identifies and implements improvements to investigation plans P12 discusses the validity and reliability of data gathered from first-hand investigations and secondary sources P13 identifies appropriate terminology and reporting styles to communicate information and understanding in physics P14 draws valid conclusions from gathered data and information P15 implements strategies to work effectively as an individual or as a member of a team
You are referred to section 8.1 of the syllabus for an expanded description of outcomes P11-P14 Outcomes being assessed: The syllabus outcomes on which you will be assessed are as follows:
Assessment Components Outcomes Assessed Marks Knowledge and understanding of: P2 applies the processes 2 . The history, nature and practice that are used to test and of physics, applications and validate models, theories uses of physics and their and laws of science with implications for society and the particular emphasis on first- environment, and current issues, hand investigations in research and development in physics physics P6 describes the forces 3 . Kinematics and dynamics, acting on an object which energy, waves, fields and matter cause changes in its motion P7 describes the effect of 2 energy transfers and transformations
Skills in planning and conducting P2 applies the processes 2 1st hand investigations and in that are used to test and communicating information and validate models, theories understanding based on these and laws of science with investigations particular emphasis on first- hand investigations in physics P11 identifies and 2 implements improvements to investigation plans P12 discusses the validity 19 and reliability of data gathered from first-hand investigations and secondary sources Skills in scientific thinking, P13 identifies appropriate 10 problem-solving, and in terminology and reporting communicating information and styles to communicate understanding and conclusions information and understanding in physics P14 draws valid 8 conclusions from gathered data and information P15 implements strategies 2 to work effectively as an individual or as a member of a team Marking Scheme
Name: ______Outcome Means of attainment Possible Mark mark awarded Part A P6 Describes motion incl. rest, acceleration, rest 3 P7 Correctly identifies GPE kinetic 2 States kinetic 1 P2 Correct substitution into correct equation 2 Attempts to use correct equation 1 P14 Identify frictionless pulley and surface 2 Identify frictionless pulley or surface 1 P12 Records mass in kg 2 Records mass 1 P12 Correctly sets up apparatus 2 Sets up apparatus with some errors 1 P12 Produces tapes with clear pattern of dots showing acceleration 2 Produces tapes showing motion 1 P12 Correctly calculates net force in N 2 Calculates net force 1
P12 Accurately measures r1 and t1 values 2
Measures r1 and t1 values 1
P12 Accurately measures r2 and t2 values 2
Measures r2 and t2 values 1 P12 Accurately measures t value 2 Measures t value 1 P12 Correctly calculates acceleration in ms-2 2 Calculates acceleration 1 P13 Correctly tabulates force and acceleration 2 Records force and acceleration 1 P13 Graph of F vs a has variables on stated axes, linear scales, labeled axes, uses most of grid, correct plots, line of best fit, or 6 Graph with 5 of above, or 5 Graph with 4 of above, or 4 Graph with 3 of above, or 3 Graph with 2 of above, or 2 Graph with 1 of above, or 1 P14 Correct statement re gradient with justification 2 Correct statement re gradient 1 P13 Correct calculation of gradient 2 Attempts to calculate gradient 1 P14 Relates graph shape to F a and gradient to m 2 Relates graph shape to F a or gradient to m 1 P12 Detailed correct discussion of validity 3 Correct discussion of validity 2 Discussion of validity 1 P12 Makes points re reliability plus value judgement 2 Makes points re reliability or value judgement 1 P11 Identifies 2 valid improvements 2 Identifies 1 valid improvement 1 P15 Identifies appropriate step with correct justification 2 Identifies appropriate step with attempted justification 1 P14 Provides valid conclusion 2 Attempts relevant conclusion 1 Total 50
Comments (over page): Name: ______Year 11 (Preliminary) Assessment Task 1st Hand investigation of Newton’s 2nd Law
1. Observe the demonstration of the moving trolley and describe in detail the motion you observe. ______2. Identify the energy transformation that occurs. ______
3. Refer to the attached page from a Physics study guide. Use the relevant example to calculate the acceleration of the trolley if it had a mass of 0.800 kg, and the mass on the end of the string was 100 g. ______
4. Identify any simplifications indicated in the example that do not conform to the trolley demonstration. ______
Aim To show how the net force acting on a system of fixed mass is related to the acceleration it produces.
Risk Assessment Hazard Hazpak Control measure Hierarchy of controls priority
Method (done in a group) 1. Measure and record the mass of the trolley in kg. 2. Set up the apparatus as shown in the diagram, with the mass carrier on the string and the four 50 g masses on the trolley. Have it checked before proceeding. 3. Label the ticker tape ‘50 g run’. 4. Hold the trolley, with the ticker tape attached, next to the ticker timer. Start the ticker timer and release the trolley. Stop the trolley before it hits the pulley, stop the timer and remove the tape. Compute and record the net accelerating force in Newtons. (W = mg) 5. Create a tape for each person in your group. 6. Transfer a 50 g mass from the trolley to the mass carrier. 7. Repeat step 4 and label the tape ‘100 g run’. 8. Repeat the above process to obtain tapes for 150 g, 200 g and 250 g runs. Analysis (done individually) Acceleration will determined by calculating an initial speed u near the start of the tape, a final speed v near the end of the tape and then the acceleration of the tape (using aav = (v – u/)t). Show all calculations performed.
1. Measure in metres the distance of a segment containing 5 consecutive spaces between dots near the start of the tape. Determine the time taken for this interval given that there is 0.02 s between consecutive dots.
2. Calculate an initial speed for this tape using u = r1/t1
3. Measure the distance in metres of a segment containing 5 (if convenient) consecutive spaces between dots neat the end of the tape. Determine the time taken for this interval given that there is 0.02 s between consecutive dots.
4. Calculate a final speed for this tape using v = r2/t2
5. Determine the time taken for this speed change to occur (ie, how many spaces between dots between the end of the first segment and the end of the second segment?).
6. Calculate the acceleration of the trolley using aav = (v – u)/t
7. Repeat steps 1-6 for each tape, tabulating all relevant data.
8. Tabulate the net force (in N) and the acceleration (in ms-1) for each run.
9. Plot a graph of net force (in N on the vertical axis) against acceleration (in ms-1 on the horizontal axis) and draw a straight line of best fit.
10. What does the gradient of the line of best fit represent? Justify your answer.
11. Calculate the gradient of your line of best fit. 12. Compare your results for steps 9 and 11 with that expected from theory.
13. Discuss the validity of this investigation.
14. (i)Assess the reliability of this investigation.
(ii) What improvements to the Method could be made to improve the reliability of this experiment?
15. Identify which step(s) in the Method for which it was more effective to work as a member of a team (Justify your answer).
16. Write a valid conclusion for this investigation.