Wahyuni, Sri2013-07-032013-07-032013-07-03http://repository.unri.ac.id:80/handle/123456789/4073Pengembangan Alat Percobaan Listrik Magnet IPA Fisika SMPThe aim of this study was to develop the instrument to make magnet by electromagnetic and to determine the Lorentz force in teaching and learning process of science at junior high school. Type of research is R & D (research and development). The development of this experiment includes the study of introduction, literature study, planning, development, validity and practicalities. The instrument that was developed is the instrument and the manual user. Based on the description of the data, is was obtained that the validation of the instrument is 84% and the manual user has 82,2% validation while the validation of the construction is 81,3% with the excellent category. The data that was obtained from the practical experiment showed the excellent level with the level of the percentage is 89% and the manual user is 82%, so that this instrument is recommended to use in teaching and learning process at Junior High School.en-USthe instrument of Electromagnet,Lorentz Forcestudent Paper Post Degree