Year 11 Physics I.D

Year 11 Physics I.D.

Time allowed: 45 minutes Mark _____ / ______ Write your name or student I.D. on each page.  Questions 1 and 2 will require you to move to one of the workstations located around the outside of the room. Each of these tasks should take you no more than 3 minutes to complete.  Answer all questions in the spaces provided.  Formulas and Data Energy = VIt P=VI R = V/I E = cmT Specific heat of water, c = 4200 J kg-1 K-1

1. Sprinkle iron filings onto the cardboard beneath which one or more magnets has been placed. Using lines to represent the field, draw the magnetic field pattern observed and show how the magnet/s below the cardboard would be positioned to account for the observed field pattern. 3

2. The apparatus in this task has three identical miniature lamps connected to three terminals across which a voltage can be applied. The way in which the lamps are connected to the terminals is concealed. Apply a voltage across every possible combination of pairs of the terminals in turn and record your observations in a table. Draw a diagram to show how the lamps must be connected [to the three terminals] to account for your observations. 6

Practical and Processes Assessment Task 2005  Year 11 Physics I.D.

3. A compass was placed clear of any magnetic objects and the orientation of the pointer was observed to be as shown in figure I below. A bar magnet was placed near to the compass as shown in figure II and the pointer moved to the position shown.

Figure I Figure II (a) Deduce the polarity of the magnet closest to the compass. 1 ...... (b) Show by drawing an arrow at X the direction in which direction the north end of the compass needle would point if the compass was placed with its centre at the point X in the diagram. 1

4. The current was to be measured through each of the two lamps shown in the circuit below on the left.

Sketch on the right hand diagram how the two meters would be placed in the circuit on the right to achieve this goal. 2

5. Consider the following circuit consisting of three identical lamps connected to the DC terminals of the power supply.

(a) Draw a circuit diagram for this circuit in the box above. 2 (b) Compare the currents through each of the light globes and justify your answer. 2 4 ...... 6. A student conducted an investigation to examine the relationship between voltage and current for a standard light globe. (a) Complete the picture below by drawing in lines to represent the appropriate connecting wires to show how the components would be connected to perform this investigation. 2

[Question 6 continues on the next page]

(b) The following results were collected by the student. Placing the independent variable on the horizontal axis, graph the data and draw in the line of best fit for this data,. 4

Table Showing Voltage – Current Relationship for the Lamp

Voltage 2.2 4.0 5.8 7.7 9.5 11.4 Current 0.8 1.4 1.9 2.3 2.6 2.8

(c) With reference to the electrical properties of the lamp, explain the shape of the graph. 2 ......

[continues on the next page]

7. A student used the apparatus shown to perform a first-hand investigation to take measurements to determine the electrical energy transformed by a heating coil in water. The water was placed in an insulating foam plastic cup. The following results were recorded. Voltage = 8.2 V Current = 3.6 A Time for which transformer was switched on = 10 minutes

(a) Calculate the electrical energy used by the circuit. 2 2

2 ......

(b) The student measured the change in temperature of the water and used an appropriate equation to calculate the heat energy gained by the water. This was found to be 12000 kJ. Account for this result, with reference to the law of conservation of energy. 3 ......

[end of paper]

Practical and Processes Assessment Task 2005  Physics Practical and Processes Assessment Task I.D.

Marking Criteria

Question 1 Marking criteria Marks Shows the magnets in the correct orientation (long axes of magnets in line with each 3 [or 1] other) AND Shows the pattern of the field correctly between two bar magnets using lines AND Labels two like poles facing each other [1 mark deducted for lines broken and/or lines crossing/touching and/or lines not touching magnet] Shows the magnets in the correct orientation (long axes of magnets in line with each 2 [or 1] other) AND Shows the pattern of the field correctly between two bar magnets using lines [1 mark deducted for lines broken and/or lines crossing/touching and/or lines not touching magnet] Uses lines to represent a valid magnetic field pattern, even if not closely related to 1 what was observed OR sketches the pattern of iron filings reasonably accurately rather than drawing lines Sample Answers (full marks)

Question 2 Marking criteria Marks Table clearly and correctly shows observed results (identifies explicitly which lamps are 3 lit for each terminal pair and their relative brightness), AND Circuit consistent with the observations 3 Table does not clearly and correctly shows observed results (does not identify explicitly 3-4 which lamps are lit for each terminal pair and their relative brightness or table poorly constructed) but the circuit is consistent with the observations OR Table clearly and correctly shows observed results (identifies explicitly which lamps are lit for each terminal pair and their relative brightness) BUT The circuit is not consistent with the observations (incorrect connections, poorly drawn) OR The correct observations are stated but not placed in a table and the circuit is consistent with the observations Table records less than THREE steps relative brightness of globes or is otherwise 1-2 deficient in the way the information is recorded AND the diagram is only consistent with one or two observations in the table made for identified pairs of terminals. Sample Answers (full marks)

7 Physics Practical and Processes Assessment Task I.D.

Question 3a Marking criteria Marks Identifies the pole closest to the magnet as a NORTH pole 1

Question 3b Marking criteria Marks Shows an arrow at X pointing to the right, parallel to the magnet 1

Question 4 Marking criteria Marks

Correctly connects both ammeters so each will only measure the current through one 2 light bulb Connects only one ammeter correctly so it will measure the current through one light 1 bulb (the other meter is connected in series with the whole circuit or connected in parallel)

Question 5 Marking criteria Marks Circuit diagram uses correct symbols, is ruled so that lines representing wires are 2 perpendicular to each other and shows lamps in parallel Diagram shows lamps in parallel but is not ruled, uses incorrect symbols or lines 1 representing wires not perpendicular to each other.

Question 5b Marking criteria Marks States that the currents through each globe are equal AND 2 Supports this deduction by recognising that this is because the lamps are all in parallel [and identical] States that the currents through each globe are equal OR 1 States that the lamps are in parallel

Question 6a Marking criteria Marks Correctly connects the ammeter in series with the lamp and the voltmeter in parallel 2 across the lamp Correctly connects either the ammeter in series with the lamp OR the voltmeter in 1 parallel across the lamp

Question 6b Marking criteria Marks Graph has axes clearly labelled with units ; voltage is on the horizontal axis; points are 4 plotted correctly and are clearly visible; appropriate curve of best fit is drawn. Graph is missing one of the above criteria OR is poorly drawn (non-linear scale, uses 3 less than half of graph paper) Graph is missing two of the above criteria OR is missing one of the above criteria and is 1-2 poorly drawn (non-linear scale, uses less than half of graph paper)

Question 6c Marking criteria Marks Clearly describes the link between the shape of the graph (curve or linear) to the 2 behaviour of the lamp filament as a non-ohmic or ohmic conductor and relates this to the increase in resistance (or constant resistance if graph is linear) due to the heating effect of the current on the filament Clearly describes the link between the shape of the graph (curve or linear) to the 1 behaviour of the lamp filament as a non-ohmic or ohmic conductor but does not relate this to the increase in resistance (or constant resistance if graph is linear) due to the heating effect of the current on the filament.

Question 7a Marking criteria Marks

Calculation uses (and shows) correct formula, substitution and final answer (including 2 units) Calculation uses (and shows) correct formula and substitution but final answer is 1 incorrect OR identifies correct final answer (and units) without showing formula and substitution.

Question 7b Marking criteria Marks Clearly demonstrates an understanding of the law of conservation of energy (stated or 3 explicit) and relates the law to the difference between their calculated value for electrical energy input and the actual heat increase of the water by outlining a valid reason (eg energy is “lost” into the atmosphere through the opening of cup and therefore the heat increase of the water will be less the energy input into the system) Demonstrates an understanding of the law of conservation of energy (stated or explicit) 2 but does not clearly relate the law to the difference between their calculated value for electrical energy input and the actual heat increase of the water by outlining a valid reason. States the law of conservation of energy OR outlines a valid reason for the difference 1 between the two calculated values.

August 11th 2005 Day 3

Period 3

Changes Room 1 9G Science – Robson – to room 16 Room 2 11 Chem – Cantor – to room 20 Room 3 11 Phys – Pitt – to room 15 (computer room)

Period 4

Changes Room 1 None – 11 Physics - Robson Room 2 8I – Cantor to room 26 Room 3 11 Primary Industries – Houweling to room 30

Supervising teacher checklist

 Mark roll attached to brown envelope (Rm 1 Robson, Rm 2 Pitt, Rm 3 Coombes)  Write starting / finishing times on board  Check equipment periodically to see that it is all OK  Collect papers at end and place them in the brown envelope and return them to Bill

 Setup instructions

In each lab

For question 1 Equipment to be set up (4 of each in each lab) Tray with magnets inside placed upright on newspaper. Iron filing sprinkler jar. Dry cloth for students to brush iron filings off the cardboard.

For question 2 Equipment to be set up (3 of each in each lab) The circuit cards (the new ones with the little light bulbs) 3 alligator clip leads (one spare) TR unit

Instructions: question 1 You should spend no more than two minutes on this investigation. Do not move the tray with the cardboard on top of it (it’s delicate) Wipe the iron filings off the cardboard onto the newspaper with the dry cloth when you have completed your observations.

Instructions: question 2 You should spend no more than three minutes on this investigation. Conduct this investigation using 12 V DC. When you have finished…  Turn off the transformer  You may leave the alligator clips attached to the transformer  Disconnect the alligator clips from the circuit card