A doctor of physics at the National Institute of Sciences (LIPI) shook his head when reading a physics textbook for junior high school students. He was surprised by errors he found in a volume 1 physics textbook published by PT Multi Trust, Jakarta. On page 64, for example, the author describes a boy throwing a ball 60 meters high when he is trying to explain vertical force. "This is a ridiculous example and does not stimulate a learner’s lo...