槓桿的種類

第一種槓桿(支點在中間)：可能省力、省時或操作方便。

   省時的理髮剪：(抗力臂<施力臂)

省力的修枝剪：(施力臂>抗力臂)

不省力不費力的天平：(施力臂=抗力臂)

第二種槓桿(抗力點在中間)：必定省力。

省力的釘書機：(抗力臂>施力臂)

省力的開瓶器：(施力臂>抗力臂)

第三種槓桿(施力點在中間)：可能省時或操作方便。

費力但方便的筷子：(施力臂<抗力臂)

費力但方便(加大作業範圍)釣竿：(施力臂<抗力臂)

費力但方便(加大做功距離)的球棒：(施力臂<抗力臂)

圖片來源：

Illustration Of Lever With Fulcrum Between The Effort And Load. [Photograph]. Retrieved from Encyclopædia Britannica Image Quest.http://quest.eb.com/images/118_825285
Illustration Of Lever With Fulcrum At One End.[Photograph]. Retrieved from Encyclopædia Britannica Image Quest.http://quest.eb.com/images/118_818281
Illustration Of Lever With Effort Exerted In The Centre. [Photograph]. Retrieved from Encyclopædia Britannica Image Quest.http://quest.eb.com/images/118_830637
BARBER SHOP. - Wood Engraving, American, 19th Century.. [Fine Art]. Retrieved from Encyclopædia Britannica Image Quest.http://quest.eb.com/images/140_1635660
Cutting Boxwood Bush Into Shape With Pruning Shears. [Photograph]. Retrieved from Encyclopædia Britannica Image Quest.http://quest.eb.com/images/118_823309

Paper Stapler. [Photograph]. Retrieved from Encyclopædia Britannica Image Quest.http://quest.eb.com/images/118_798357
Bottle Opener, Action. [Photography]. Retrieved from Encyclopædia Britannica Image Quest.http://quest.eb.com/images/156_2406920
Woman Eating With Chopsticks. [Photography]. Retrieved from Encyclopædia Britannica Image Quest.http://quest.eb.com/images/154_2886722
Sea Match Fisherman Holding Fishing Rod.[Photograph]. Retrieved from Encyclopædia Britannica Image Quest.http://quest.eb.com/images/118_808405
Boy Swinging Baseball Bat At Ball. [Photography]. Retrieved from Encyclopædia Britannica Image Quest.http://quest.eb.com/images/154_2886734
BALANCE SCALE. [Photograph]. Retrieved from Encyclopædia Britannica Image Quest.http://quest.eb.com/images/148_1831166