Ever rub your hands together and notice that they warm up? That's friction, the force resisting the relative motion of solid surfaces, fluid layers, and/or material elements sliding against each other. Friction creates heat which can create a small flame if on a dry surface.

In fiction however, particularly animation, friction can cause one to [[IncendiaryExponent burst into flames]]. This is usually PlayedForLaughs and is often caused by a character's own [[TooDumbToLive stupidity]]. In superhero fiction, characters with SuperStrength might do this. One of the RequiredSecondaryPowers of characters with SuperSpeed must be dedicated to avoid this. This trope may also be in effect when someone is using a FingerSnapLighter, or when BurningRubber.

Compare PlayingWithFire, when this trope is weaponized. Contrast FrictionlessReentry, which is the opposite of this trope. Related to SpaceFriction.

----
!!Examples

[[AC: {{Anime}} and {{Manga}}]]
* In ''Manga/OnePiece'':
** This is how [[ChefOfIron Sanji]] activates his ''[[GratuitousFrench Diable Jambe]]'' technique.
** Also, this is supposedly how [[TheStarscream Hannyabal]] activates his ''Hannya Carnival, Blazing Hell Wheel'' attack.
** This may also be how [[MasterSwordsman Zoro's]] ''Hiryu Kaen'' attack works.
* In ''[[LightNovel/BakaToTestToShoukanjuu Baka and Test]]'', LoveableSexManiac Kouta is always trying to take pictures of the girls, always searching for a glorious PantyShot. When he senses the opportunity to get a shot from Mizuki, he starts sliding all around her on the floor, trying to get the perfect angle. He sets himself on fire from the friction, then dowses himself with his own blood from the {{Nosebleed}} that followed afterward.
* Invoked in ''RozenMaiden'' whenever Micchan gets a bout of CutenessProximity dressing up Kanaria and rubs her cheeks against hers. Worse for Kanaria, since, being a doll, she's made of quite flammable material and while she never actually bursts into flames, it's clearly not comfortable for her.
* In ''LightNovel/{{Durarara}}'': Mikado Ryugamine uses the internet so epically that his [[http://i726.photobucket.com/albums/ww262/CapZiggy/vlcsnap-2010-03-15-22h18m45s103.png mouse catches on fire]] from the friction.
* In ''Manga/FairyTail'', the [[GoldfishPoopGang Jiggle Butt Gang]] escape from the Zentopia dungeons by using this to light their asses on fire…ItMakesJustAsMuchSenseInContext.
* Invoked ''hard'' in ''Manga/{{GUNNM}}''. In her previous life, Alita had been sentenced to death by Atmospheric Exposure - meaning she was tossed out an airlock in a decaying orbit to burn up in reentry.

[[AC: WebComics]]

* ''WebComic/{{Irrelevator}}'' [[http://i.imgur.com/7Ra7yxQ.gif Happens to the Red guy. ]]

[[AC: WesternAnimation]]
* In an episode of ''PowerpuffGirls'', Buttercup created a fireball by rubbing her hands together rapidly and threw it at a monster.
* In an episode of ''WesternAnimation/FamilyGuy'', Peter drank Red Bull, giving him a rush of energy, and then milked a cow so rapidly, its udder burst into flames. In the same scene Chris, who also drank Red Bull, was seen running around screaming, pantsless and [[ADateWithRosiePalms his groin ablaze]].
* ''WesternAnimation/TheAmazingWorldOfGumball'' gives us an example where Gumball is trying to start a fire through the friction & stick method. He ends up setting his hands on fire, and while he's running around screaming in pain, the wood he was trying to ignite catches on fire a few moments later. CueTheRain.
** He also caught on fire from air friction when going down a hill too fast, while the friction with the ground tore the bike apart.
* In ''WesternAnimation/DextersLaboratory'', when Dexter gives himself SuperSpeed to go through his whole daily routine in 1 minute he accidentally lights his homework on fire from the friction (and called it by the trope name at that).
* In ''TheProudFamily'', Oscar sets his hand on fire while trying to snap. [[LampshadeHanging A few seconds prior, a kid warned him about trying to snap because his skin was so dry.]]
** Similar, while in the middle of a MachoDisasterExpedition he remember how his mother always said his ankles were so ashy they could start a fire, so he tries it--and it works!
* On the WesternAnimation/RogerRabbitShort "Roller Coaster Rabbit", Roger's feet catch fire while skidding down a roller coaster track.
* On the short-lived superhero spoof series ''TheRippingFriends'', the main characters accidentally make Frictor, a malevolent friction ''elemental''. He can cause friction burns strong enough to disintegrate anything (or any''one'') in his way, though Frictor mainly uses his control over friction for [[PokeThePoodle dumb pranks]].
----