Many children find it difficult to change physics in the third year of junior high school. They can't do anything about electricity problems, and they will lose scores if they neglect them a little. According to the distribution of physical scores in the midterm exams in these years, mechanics and electricity are almost the same. Under the 100 point system, the general content of mechanics is more than 30 points, and the content of electricity is close to 40 points. Parents may not understand the specific distribution of physics in junior three, and think that physics in junior three is not improved much compared with that in junior two. So, is it difficult to learn electricity in junior high school physics?
Is it difficult to learn electricity in junior high school physics
Overall, it is difficult for children. First of all, all the concepts in children's electricity are too abstract to see or touch. None of the students have ever seen "charge", and "current" can only be imagined. "voltage", "resistance", not to mention "electric energy", "electric power", and so on. These concepts can not see anything in real life, It can only be understood indirectly through comparison, comparison, transformation, etc.
How to learn electrical knowledge in junior high school
1. Start with basic concepts
Children in the third day of junior high need to read carefully about electricity, ask more why, and develop self-learning ability. Reading of textbooks. It mainly includes reading before class, reading in class and reading after class. Read before class and think while reading according to the different contents of the textbook and the questions raised in the text. Through reading, we can have a rough understanding of the content of the new lesson, clarify the knowledge points, find out the key points and difficulties, and make marks so as to break through and overcome the difficulties when listening to the teacher's explanation in class. Classroom reading is to read in the process of a new lesson, and remember the key knowledge while reading.
2. Comprehensible memory formula and law
Most students believe that physics is a science subject, as long as they can do it, but they do not know that the premise of doing it is to remember formulas and laws. When children are just exposed to electricity, they think it is simple. Once they reach the Ohm's law, electric power, Joule's law and comprehensive application, they do not know how to apply the formula and law. So, how to remember formulas and laws for a long time? Is to understand memory. For example, Ohm's Law: the current passing through a conductor is proportional to the voltage at both ends of the conductor and inversely proportional to the resistance of the conductor. How to understand Ohm's law? Voltage is the cause of current formation. If there is current, there must be voltage. Voltage affects current, so current is proportional to voltage.
3. Master the general steps of problem solving
In the electricity comprehensive question, when students see a more complex circuit diagram, they don't know where to start. In view of this situation, we need to simplify the circuit and analyze the connection mode of the circuit (series, parallel). Think of the ammeter as a wire and the voltmeter as an open circuit, that is, the voltmeter is not in the circuit.
4. Integrating theory with practice in life
For example, if you don't work hard, how can you know how to use labor tools to save labor, and how can you learn the lever principle well; How can children understand "short circuit" and "open circuit" without connecting the circuit? They will not feel "electric heat" without connecting the circuit. They will not know whether it is "series connection" or "parallel connection" without observing the street lights. Only children learn physics, combine the observed phenomena with their own experience, and learn theory. It will be interesting and simple to learn electrical knowledge, rather than the more difficult it is to learn.
To learn physics and electricity well, children should first learn the simple equations in mathematics, and then start to remember the basic concepts and understand the formulas and laws. It is suggested to learn physics and electricity by comparison, and then think and practice more. It is not difficult to learn physics well by using both hands and brain.
