运用投影仪进行磁力线演示,具体作法是:在投影仪的水平镜面上放置一稍大的平板透明玻璃,先用手撒一层铁屑,通过投影仪在屏幕上显示了铁屑杂乱无章的排列,然后用手轻轻水平托起玻璃,把条形磁铁(或蹄形磁铁、同名磁极磁铁、异名磁极磁铁)放入玻璃板下,再轻轻振动玻璃板,这样铁屑在磁场中由于受到磁场 Use the projector to demonstrate the magnetic field lines by placing a slightly larger flat transparent glass on the horizontal mirror surface of the projector, spreading a layer of iron scraps by hand, and displaying the disorderly arrangement of the iron chips on the screen by the projector. Then, gently hold the glass horizontally by hand, place the bar magnet (or the shoe magnet, the magnet of the same name, or the magnetic pole of the same name) under the glass plate, and gently vibrate the glass plate so that the iron chip is subjected to the magnetic field in the magnetic field.