Bahan Sumber Inkuiri SAINS Bahan Sumber Inkuiri Sains Menengah Rendah 96 Student’s Worksheet 17.1 Aim: TO MEASURE BACKGROUND RADIATION WITH DOSIMETER Step 1: Dosimeters is used to measure background radiation in units of µSv / h. Press the dosimeter provided and place it in front of you. Is the reading value lower or higher than the world average dose rate? Dosimeter reading: Step 2: Place the dosimeter on a different surface. Record the readings in the table below: No. Types of surface Dose rate in µSv/j Dose rate in mSv/thn Dose absorbed in 50 years 1 2 min 1 Granite 2 Salt 3 Soil from hot springs 4 Limestone 5 Paint 6 Car dashboard 7 Bitumen road State your observations. What conclusions can be drawn from the results of your observations? Teacher guides the pupils to the conclusion
Bahan Sumber Inkuiri SAINS Bahan Sumber Inkuiri Sains Menengah Rendah 97 ASSESSMENT ITEMS Performance Level 1 (Recall the knowledge and basic scientific skills) 1. Match the scientist to their contributions in radioactivity. For question 2 – 6, use the following choices to answer the questions. There are answer choices that will be use more than once. 2. Radioactivity ia a spontaneous ___________ process whereby an _____________ nucleus emits _____________ radiation. 3. ___________________ of a radioactive decay is the time for the radioactive materials to become half of its original value. 4. Radioactive sources emit three types of rays that is ________________, _____________ and ___________ 5. The structure of an atom consist of thre particles that is ____________, ____________ and ____________ Unstable Decay Radioactive Half-life Proton Alpha Electron Gamma Neutron Beta proton electron on proton Marie dan Pierre Curie Henri Becquerel Wilhelm Roentgen X-Rays Radioactive elements Radioactivity radioactive decay unstable Half-life alpha beta gamma neutron
Bahan Sumber Inkuiri SAINS Bahan Sumber Inkuiri Sains Menengah Rendah 98 6. An atom is neutral whereby the number of ____________ equals to the number of _____________. Nota (Untuk Guru): Guru boleh menambah soalan bagi standard pembelajaran 8.3.2 yang menunjukkan perbezaan antara ketiga-tiga sinaran dari aspek saiz zarah, kuasa pengionan, kuasa penembusan, pemesongan oleh medan magnet dan elektrik. Performance Level 2 (Understand the knowledge and scientific skills and able to explain their understanding) 1. Give three examples of radioactive materials. 2. Why do spontaneous decay occurs in radioactive materials? 3. Describe how positive ions are formed? 4. Explain how background radiation exist? 5. Which activity causes the highest exposure to natural background radiation? A. Breathing fresh air B. Lying on the beach C. Eating ice cream D. Using the computer Carbon-14, Radon-222, Thorium-232, Uranium-235 To become more stable When an atom losses or releases electron Background radiation is the result of small amounts of radioactive material in rocks, soil and water and partly due to cosmic ionizing radiation coming from outer space. electron proton
Bahan Sumber Inkuiri SAINS Bahan Sumber Inkuiri Sains Menengah Rendah 99 PERFORMANCE LEVEL 3 (Apply the knowledge and scientific skills to accomplish simple task) Gamma rays is an ionising radiation that has the highest penetrating power compared to alpha and beta rays. Gamma rays can be stopped by a 10 cm plumbum block. Suggest safety features of the container to keep radioactive waste and where it should be stored. Safety features of the container for radioactive waste: Storage area: PERFORMANCE LEVEL 4 (Analyse the knowledge and scientific in context of problem solving about events or natural phenomena) The total worldwide average effective dose from natural radiation is approximately 2.4 mSv per year. a) What would be the dose rate in µSv/hr? Storage containers for radioactive wastes made from stainless steel or radioative material solidified with concrete or bitumen before planting or burying. The containers must be labelled with radioactive symbol. Away from corrosive, explosive and flammable materials. Far away from natural disaster areas. Far from water resources. 365 days -- 2400µSv 1 day – 2400/365 = 6.57 µSv/day Therefore in 1 hour = 6.57/24 µSv = 0.27 µSv/j
Bahan Sumber Inkuiri SAINS Bahan Sumber Inkuiri Sains Menengah Rendah 100 b) Referring to the table for levels of health risk radiation, what is the inference on the effect to an individual’s health that had been exposed to natural radiation for 60 years? PERFORMANCE LEVEL 5 (Evaluate the knowledge and scientific skills in the context of problem solving and decision making to carry out a task) Can using a microwave oven cause cancer if used for a long period of time? Why? PERFORMANCE LEVEL 6 (Design with creative and innovative use of science knowledge and skills in the context of problem solving and decision making with regards to the social values/ economy/ culture of the community) En. Ahmad is a construction engineer. His work is mainly outdoors in the sun. Mr. Tan teaches Physical Education and Health in a school in Kuala Lumpur . Mr. Ravi is a pilot with a local airline. Who experiences the highest exposure to background radiation? Explain your answer and suggest one way to minimize risks. Total exposure = 60 x 365 x 24 x 0.27 µSv = 141 012 µSv Therefore in 1 hour = 141 912 µSv/60 x365 x 24 hours = 0.27 µSv/h 0.27 µSv/h is safe at normal level No Microwaves are non-ionising radiation Mr. Ravi High altitude causes exposure to more cosmic radiation. To reduce the risks, Mr Ravi need to work on shifts and regular basis.
Bahan Sumber Inkuiri Sains Menengah Rendah 101 Writers 1. Aizatul Adzwa binti Mohd. Basri Bahagian Pembangunan Kurikulum 2. Azmi bin Harun Bahagian Pembangunan Kurikulum 3. Kasdi bin Kamin Bahagian Pembangunan Kurikulum 4. Mohd. Osmira bin Mohid Bahagian Pembangunan Kurikulum 5. Ruslawati binti Mat Isa Bahagian Pembangunan Kurikulum 6. Mohd Alfouzii bin Nasir JPN Melaka 7. Dr. Chua Chong Sair IPGK Sultan Abdul Halim, Sg,Petani, Kedah 8. Dr. Ooi Hean Beng IPGK Ipoh, Perak 9. Pradeep Kumar Chakrabarty SMJK Yu Hua, Kajang, Selangor 10. Rema Ragavan SMK Sultan Abdul Samad, Petaling Jaya 11. Jeyanthi a/p Annamalai SMK Seri Bintang Utara, Kuala Lumpur 12. Morgan a/l T. Vadiveloo SMK St.Paul, Seremban, 13. Lee Yuet Lai SMK Sulaiman, Bentong, Pahang 14. Yap Poh Kiut SMK Ketari, Bentong Pahang 15. Raja Faziatul Hanim binti Raja Azie SMK Seri Bintang Selatan, Kuala Lumpur 16. Soraya binti Ishak SMK (L) Methodist, Kuala Lumpur 17. Suzyana binti Hassim SMK King Edward, Taiping, Perak 18. Nadira binti Ismail SM Sains Tapah, Tapah, Perak 19. Nurul Huda binti Kasim SMK Syeikh Abdul Ghani, Bidor, Perak 20. Nor Azlinawati Binti Yaacob SABK Maahad Al Tarbiah Al Islamiah, Cangkat Jering, Perak 21. Anwaruddin bin Mohd Kasim SM Sains Tapah, Tapah, Perak ACKNOWLEDGEMENT
Bahan Sumber Inkuiri Sains Menengah Rendah 102 1. Aerma Nurazalina Binti Musa JPN Johor 2. Hairulnizam Bin Ramlan JPN Johor 3. Ku Zurisham Bin Ku Mahamad JPN Kedah 4. Mohamad Izham Bin Md Yusof JPN Kedah 5. Halizah Binti Mohd Zain JPN Kelantan 6. Zuriati Binti Abdul Rahim JPN Kelantan 7. Ismail Bin Ali JPN Melaka 8. Suzita Binti Binti Mohd Resad JPN Negeri Sembilan 9. Mohd Fadzil Bin Jamil JPN Negeri Sembilan 10. Ziaor Rahman bin Othman JPN Negeri Sembilan 11. Eszri Bin Sies JPN Pahang 12. Mohammad Shukri Bin Salleh JPN Pahang 13. Mispuah Binti Hassan JPN Pahang 14. Ahmad Redzaudin Bin Hussein JPN Perak 15. Zalina Binti Saad JPN Perak 16. Noor Nasihah Binti Abbas JPN Perlis 17. Shahanum Yanty Binti Mat Hassan JPN Perlis 18. Ruslan Bin Abd Majid JPN Perlis 19. Siti Rohayu Binti Ismail JPN Pulau Pinang 20. Molisa Binti Mukhtar JPN Pulau Pinang CONTRIBUTORS
Bahan Sumber Inkuiri Sains Menengah Rendah 103 21. Ahmad Azhar Bin Talib JPN Pulau Pinang 22. Mohd Nuzie Bin Balus JPN Sabah 23. Dg Rukayah Binti Ag Mahmun JPN Sabah 24. Haslina Binti Marzoki JPN Sarawak 25. Siti Norakma Binti Kamaruddin JPN Selangor 26. Azni @ Siti Aishah Binti Idris JPN Selangor 27. Nor Haliza Binti Omar JPN Terengganu 28. Roslia Binti Daud JPN Terengganu 29. Isa Bin Salleh JPN Terengganu 30. Mohd Nishan Bin Baharum JPWP Kuala Lumpur 31. Abi Nubli Akrami Bin Ibrahim JPWP Kuala Lumpur 32. Zamri Tiri Anak Dunggat JPWP Labuan 33. Ang Bee Uan JPWP Labuan 34. Noriah Binti Hamzah JPWP Putrajaya 35. Rohana Binti Mohamad JPWP Putrajaya
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