Ib Lab - 09 Projectile Motion (dcp Ce)

International Baccalaureate Physics

4/PSOW

Projectiles Aim: To calculate the initial horizontal take off velocity of an object that is allowed to fall after being released from a ramp.

IB Criteria Assessed Data Collection and Processing, Conclusion and Evaluation Criteria

Aspect

Level

assessed 1 2 3 awarded Method: 1. Set up the apparatus as shown below. D 2. Place the wooden board in the vertical position so that it is DCP touching the bottom of the ramp. CE 3. Release the ball bearing from height h so that it accelerates down the ramp and makes a mark on carbon paper attached to the wooden board. 4. Move the wooden board away from the ramp by a small distance (sx) and release the ball once again. 5. Repeat for 6 to 8 distances of sx.

Diagram: h = vertical height for the ball to be dropped.

ax

ux

h

sy

uy

ux = initial horizontal velocity. uy = initial vertical velocity.

ay

ax = initial horizontal acceleration. ay = initial vertical acceleration. sx = horizontal distance. sy = vertical distance. sx

Data Collection and Presentation:: • Measure distances sx and corresponding distances sy and record these values in a suitable table. Note: It is important to use fundamental units. • Include uncertainties due to the precision of the measuring apparatus. • Process your quantitative raw data. by drawing a suitable graph which will allow the initial horizontal take off velocity ux to be calculated. • Present the processed data in a appropriate way and include errors and uncertainties Conclusion and Evaluation: • Evaluate the data that you have collected and analysed - compare your results by calculating the initial horizontal take off velocity (ux) using the conservation of mechanical energy equations (mgh = ½mv2) • Evaluate the procedure, including any modifications you had to make to overcome problems. Include an evaluation of the apparatus used. • Suggest ways in which the procedure could be modified in order to improve it for the future.

© 2006 - Mike Dickinson

8356920.doc

International Baccalaureate Physics

4/PSOW

Internal Assessment Marking Form Crit.

Pl(a)

Pl(b)

DC

DPP

CE

Aspects Research Question: Hypothesis: Variables: c. Identifies a focused c. Relates the hypothesis or c. Selects the problem or research prediction directly to the relevant question. research question and independent p. States the problem or explains it, quantitatively and controlled research question, but it where appropriate. variable(s). is unclear or incomplete. p. States the hypothesis or p. Selects some n. Does not state the prediction but does not relevant problem or research explain it. variables. question or repeats the n. Does not state a n. Does not select general aim provided by hypothesis or prediction. any relevant the teacher. variables. Materials / Control of Variables: Collecting Data: Apparatus: c. Describes a method c. Describes a method that c. Selects appropriate that allows for the allows for the collection apparatus or control of the of sufficient relevant materials. variables. data. p. Selects some p. Describes a method p. Describes a method that appropriate that makes some allows for the collection apparatus or attempt to control the of insufficient relevant materials. variables. data. n. Does not select n. Describes a method n. Describes a method that any apparatus or that does not allow for does not allow any materials. the control of the relevant data to be variables. collected. Collecting / Recording Raw Data: Organising / Presenting Raw c. Records appropriate raw data (qualitative Data: and/or quantitative), including units and c. Presents raw data clearly, uncertainties where necessary. allowing for easy p. Records some appropriate raw data. interpretation. n. Does not record any appropriate raw data. p. Presents raw data but does not Aspect 1 includes units, uncertainties, allow for easy interpretation. significant digits n. Does not present raw data or presents it incomprehensibly. Processing Raw Data: Presenting Processed Data: c. Processes the raw c. Presents processed data appropriately, helping data correctly. interpretation and, where relevant, takes into p. Some raw data is account errors and uncertainties. processed correctly. p. Presents processed data appropriately but with some n. No processing of raw errors and/or omissions. data is carried out or n. Presents processed data inappropriately or major errors are made incomprehensibly in processing. Aspect 2 includes uncertainty bars, max / min slopes (HL), axes with labels and units, best fit line drawn Drawing Conclusions: Evaluating procedure(s) Improving the c. Gives a valid and results: investigation: conclusion, based on the c. Evaluates procedure(s) c. Identifies correct interpretation of and results including weaknesses and the results, with an limitations, states realistic explanation and, where weaknesses or errors. suggestions to appropriate, compares p. Evaluates procedure(s) improve the results with literature and results but misses investigation. values. some obvious p. Suggests only p. States a conclusion that limitations or errors. simplistic has some validity. n. The evaluation is improvements. n. Draws a conclusion that superficial or n. Suggests unrealistic

© 2006 - Mike Dickinson

Level ccc 3 ccp 2 ccn 2 cpp 2 ppp 1 cpn 1 cnn 1 ppn 1 pnn 0 nnn 0

Grade

ccc 3 ccp 2 ccn 2 cpp 2 ppp 1 cpn 1 cnn 1 ppn 1 pnn 0 nnn 0

cc 3 cp 2 cn 1 pp 1 pn 0 nn 0

cc 3 cp 2 cn 1 pp 1 pn 0 nn 0

ccc 3 ccp 2 ccn 2 cpp 2 ppp 1 cpn 1 cnn 1 ppn 1 pnn 0 nnn 0

8356920.doc

International Baccalaureate Physics

misinterprets the results.

© 2006 - Mike Dickinson

4/PSOW

irrelevant.

improvements.

8356920.doc