黑板







葵涌循道中學物理室之一個黑板




深綠色的黑板.


黑板是能讓粉筆於上面標記的平面，通常用作書寫。


黑板可以是一塊漆了深色顏料（通常是深綠色或黑色）的板。黑板下方通常會有一個窄長的架，能放置粉筆和黑板擦。


黑板常用於教學。用沾了水的布或黑板擦（一塊帶氈的木，或一個用布捲成的物體）便可輕易去除粉筆跡。在濕的黑板上書寫，那些粉筆跡難以抹除。



优缺点


黑板的缺點在於使用時會產生不少塵埃（就粉筆的品質而定），有些人會因此而覺得不適，甚至引致呼吸困難。可是，其他顯示資訊的方法更昂貴且亦有不足之處，所以至今黑板在教室裡仍然被廣泛使用。但在一些地方，不會產生塵埃的白板開始漸漸取代黑板。


与白板相比，黑板有如下优势：



  • 粉笔不需要额外养护；白板笔使用后需要盖上笔帽

  • 相对于白板笔，粉笔的价格更低廉

  • 粉笔气味温和；白板笔多有刺鼻气味

  • 粉笔痕迹容易被清除；长时间留在白板上的字迹需要特殊溶剂擦除

  • 织物上的粉笔可以轻易脱落；白板笔一般会对布料形成永久性染色



相關條目



  • 粉筆

  • 白板

  • 電子白板



外部連結






维基共享资源中相关的多媒体资源：黑板

  • 黑板也會反光? (物理)








规范控制


  • GND: 4179987-2

  • NARA: 10662872

  • NDL: 00576002



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