Placeholder Image

字幕列表 影片播放

  • Smart Learning for All

  • Topic: Electric Charge.

  • How does a plastic comb attract paper?

  • What?

  • You don't believe me?

  • Ok.

  • Let us try.

  • Take a plastic comb and bring it close to some pieces of paper.

  • Hey, Wait.

  • Don't laugh.

  • We need to do something first.

  • Rub the comb on your dry hair and then bring the comb close to the pieces of paper.

  • See, I was correct.

  • The pieces of paper got attracted to the plastic comb.

  • Do you think it is magic?

  • No, the reason behind this is electric charge.

  • Electric charge is the quantity of electricity held in an object.

  • There are 2 types of electric charges, positive and negative.

  • However, there are some objects where the positive and negative charges are equal to one another.

  • In such cases, we say that the object is electrically neutral.

  • So, was the plastic comb initially electrically neutral or electrically charged?

  • Initially, the plastic comb was electrically neutral.

  • That means it had equal number of positive and negative charges.

  • Hence, it did not have the ability to exert a force and attract the pieces of paper.

  • So, after rubbing the plastic comb on our dry hair, why was it able to attract the pieces of paper?

  • I will tell you why.

  • When we rubbed the plastic comb on our dry hair, it gained an electric charge.

  • Once it got electrically charged.

  • It got the ability to exert a force on the pieces of paper and attract them.

  • This charge is called as static electricity.

  • However, do you think, like a plastic comb, a metallic comb will also attract the pieces of paper?

  • No, you are wrong.

  • A metallic comb will not attract the pieces of paper like the plastic comb.

  • Wondering why is that so?

  • It is because plastic is not a good conductor of electricity.

  • It does not allow the electric charges to flow through it onto the earth.

  • As a result, the charges build in the plastic comb.

  • Making it electrically charged and enabling it to attract the pieces of paper.

  • However, metal is a good conductor of electricity.

  • It does not let the charges build in it.

  • It allows the electric charges to flow through it onto the earth.

  • Thus, not allowing the metallic comb to get electrically charged.

  • As a result, the metallic comb does not attract the pieces of paper.

  • For more educational videos please visit http://www.SmartLearningforAll.com

  • Also, don't forget to subscribe to our YouTube channel.

Smart Learning for All

字幕與單字

影片操作 你可以在這邊進行「影片」的調整,以及「字幕」的顯示

B1 中級 美國腔

塑膠梳子是如何吸引紙張的?| 梳子是如何吸引紙張的? (How does a plastic comb attract paper? | #aumsum)

  • 13 1
    AumSum 發佈於 2021 年 01 月 14 日
影片單字