# Acme Dynamite Plunger

**URL:** <https://boards.straightdope.com/t/acme-dynamite-plunger/349422>\
**Category:** Factual Questions\
**Created:** [March 22, 2006, 1:26pm UTC](https://boards.straightdope.com/t/acme-dynamite-plunger/349422 "2006-03-22T13:26:14Z")\
**Posts on this page:** 4\
**Page:** 1

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**Author:** ![HMS\_Irruncible](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/hms_irruncible/32/7394_2.png) [@HMS\_Irruncible](https://boards.straightdope.com/u/HMS_Irruncible)\
**Post date:** [March 22, 2006, 1:26pm UTC](https://boards.straightdope.com/t/acme-dynamite-plunger/349422/1 "2006-03-22T13:26:14Z")

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So in the old Bugs Bunny cartoons, Rube Goldberg contraptions, and Three Stooges reruns, we see that a dynamite explosion is often initiated by a box with a plunger that is actuated by pushing downward.

My question is, why the plunger and what does it do? I’m led to understand it’s called a “dynamo” which is a sort of electric generator but I can’t figure how the plunger arrangement creates and delivers the charge in the correct way.

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**Author:** ![CalMeacham](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/calmeacham/32/35_2.png) [@CalMeacham](https://boards.straightdope.com/u/CalMeacham)\
**Post date:** [March 22, 2006, 1:30pm UTC](https://boards.straightdope.com/t/acme-dynamite-plunger/349422/2 "2006-03-22T13:30:43Z")

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We’ve had a few threads on these. Here’s one:

[http://boards.straightdope.com/sdmb/showthread.php?t=257431&highlight=plunger+explosive](http://boards.straightdope.com/sdmb/showthread.php?t=257431&highlight=plunger+explosive)

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**Author:** ![Q.E.D](https://avatars.discourse-cdn.com/v4/letter/q/51bf81/32.png) [@Q.E.D](https://boards.straightdope.com/u/Q.E.D)\
**Post date:** [March 22, 2006, 4:48pm UTC](https://boards.straightdope.com/t/acme-dynamite-plunger/349422/3 "2006-03-22T16:48:23Z")

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If you don’t feel like clicking the link, the short, simplified version is that the plunger turns the dynamo and an energy-storing flywheel as it’s pushed down by engaging a straight gear on the plunger rod with a pinion gear on the dynamo. When the the plunger reaches the bottom of its travel, it depresses a switch which closes the circuit. BOOM. Coyote is toast.

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**Author:** ![Dervorin](https://avatars.discourse-cdn.com/v4/letter/d/eb8c5e/32.png) [@Dervorin](https://boards.straightdope.com/u/Dervorin)\
**Post date:** [March 22, 2006, 11:07pm UTC](https://boards.straightdope.com/t/acme-dynamite-plunger/349422/4 "2006-03-22T23:07:49Z")

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> [@Q.E.D.](#):
>
> If you don’t feel like clicking the link, the short, simplified version is that the plunger turns the dynamo and an energy-storing flywheel as it’s pushed down by engaging a straight gear on the plunger rod with a pinion gear on the dynamo. When the the plunger reaches the bottom of its travel, it depresses a switch which closes the circuit. BOOM. Coyote is toast.

Coyote? Toast? Surely not. Nothing appears to daunt that member of the canine race; he just gets covered in soot and goes off, coughing slightly, to plan his next dastardly attack on the Road Runner.

Wile E. Coyote always got my sympathy - he was always getting beaten up, without any reward whatsoever.

[/hijack as the OP seems to have been answered] 😃