电磁打点计时器(下称打点器)是高中力学中重要的实验仪器。如果实验时打点不清晰,既耗时间、费纸带,又影响教学效果。本文就如何使这种打点器打点清晰的问题,作一探讨和介绍。 1 打点器打点清晰的必备条件要使打点器打点清晰,应具备如下几个条件: (1)提供合适的工作电压(一般是低压交流电6～8伏),衔铁的压力要调整适度,在通电工作时,能听到均匀、清脆的嗒嗒声响。 (2)使用的复写纸要看上去鲜亮,有一定的湿度。 (3)纸带走动时,能带动复写纸转动。若满足这三个条件,一般说来,打点的纸带能符合 Electromagnetic strike timer (hereinafter referred to as ticker) is an important experimental instrument in high school mechanics. If the test is not clear, it will not only take time and cost, but also affect the teaching effect. This article makes a discussion and introduction on how to make this type of ticker clear. 1 The necessary conditions for the operator’s clearing of the indenter should make the inker clear, and should have the following conditions: (1)Provide the appropriate working voltage (usually low voltage alternating current 6 to 8 volts), the pressure of the armature should be adjusted moderately, When working on electricity, you can hear a uniform, crisp buzzing sound. (2) The used carbon paper should look bright and have a certain humidity. (3) When the tape moves, it can drive the rotation of the carbon paper. If these three conditions are met, in general, the dotted tape can meet