Towards the end of the movie when Marty is driving down the street in 1955 to go back to 1985, Doc is trying to get the electricity cables back together for the lightning needed to send Marty back to the future. Doc then slides down the cable to connect the cable to the other one over the street. As he's about to connect the cable, the lightning strikes. He then has at least half a second to connect the cable and he does. But the lightning takes at least two seconds to get from the tower to the car. This is way to slow for electricity. Electricity can move around the world four times in a second. [The velocity of electric current depends very much on the insulation of the wiring being used. For instance, in open air (such as lightning) electricity is very fast, but within rubber-insulated wiring, it is slower.] Corrected by JC Fernandez
Back to the Future (1985) - 94 corrections
Directed by Robert Zemeckis, starring Christopher Lloyd, Crispin Glover, Lea Thompson, Michael J. Fox, Thomas F. Wilson
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Towards the end of the movie when Marty is driving down the street in 1955 to go back to 1985, Doc is trying to get the electricity cables back together for the lightning needed to send Marty back to the future. Doc then slides down the cable to connect the cable to the other one over the street. As he's about to connect the cable, the lightning strikes. He then has at least half a second to connect the cable and he does. But the lightning takes at least two seconds to get from the tower to the car. This is way to slow for electricity. Electricity can move around the world four times in a second. [The velocity of electric current depends very much on the insulation of the wiring being used. For instance, in open air (such as lightning) electricity is very fast, but within rubber-insulated wiring, it is slower.] Corrected by JC Fernandez Marty McFly shows up in 1955 America and walks around with a *digital watch,* and no one asks to see it. [All that means is that nobody particularly noticed it. Which isn't that unreasonable; how often do you look closely at somebody's wrist?] Corrected by Tailkinker When Marty goes back to Nov. 5, 1955, the time is set for 8:30 AM. When he arrives he walks around a bit in amazement and then heads towards Hill Valley. The sign he passes says "Hill Valley 2 miles." When he gets there, look at the clock tower, the time is about 8:30 (give or take). He couldn't have run the two miles in under a minute even without hiding the DeLorean. [No such thing occurs. When he's being chased by the Libyans at the mall, the display reads the destination time at sometime during the 6 o'clock hour (the minutes are not visible). This is the last time we can see the precise time on the time circuit display until the night of the storm. Regardless, in the scene in question, the time circuits are out of power and malfunctioning so they could have given a false reading.] Corrected by JC Fernandez In the beginning, when Doc awakens Marty in the beginning he tells him to meet him at "Lone Pine Mall" (the altered name of the mall after the movie) but when Marty arrives at the mall the sign still reads "Twin Pines Mall". How come Doc is referencing the new name that hasn't changed yet? And this scene occurred just before any time traveling took place so it's definitely not a paradox (most likely a script error). [I think you need to check again. First of all, Doc does not "awaken" Marty. Marty is visiting Doc's house, and has been trying out the gigantic loudspeaker (knocking himself backwards). Second, Doc clearly says "Twin Pines Mall", and has done so in every version of the movie I have ever seen.] Corrected by Twotall Just after the Libyans arrive, Marty is seen jumping into the Delorean. If you look closely at his face in this shot, you can see that it's not Michael J. Fox. It's actually Eric Stolz, who was originally cast as Marty McFly. [This has already been corrected once. When Michael J Fox took over the role, the costume was changed. Stoltz's Marty wore black Converse shoes in 1985 (as seen in behind the scenes photos), but when Fox took over the role, the character's shoes were changed to white Nikes. The person leaping into the Delorean wears white Nikes - it is definitely NOT Eric Stoltz.] American police may be so lackadaisical that they don't attend the scene of a car racing noisily around a car park, followed by a loud crash of a van hitting a shed, but I find it hard to believe that they don't investigate continuous machine gun fire from the same area. There are occupied building all around the car park, and there is plenty of time for them to turn up. [They'd have to receive a call from someone to be made aware of the situation. If the neighbors thought it was just some teenagers screwing around with firecrackers, which is more likely (because how often to Libyan terrorists open fire right next door?), the police wouldn't exactly rush to the scene lights blazing and sirens blaring. There's very few minutes from when the Libyans start firing to when Marty goes back to 1955, and who knows how far away the nearest police cruiser is.] Corrected by Phixius When Marty is being chased by the terrorists, he disappears through time, and the terrorists crash their van into the photo-booth, which presumably stops them dead in their tracks. But really, how would trashing that small booth make the bad guys irrelevant from that point onward? They weren't killed. So realistically they'd all get out of their crashed van and proceed to wreak more havoc. Yet in the time it takes Marty & Doc Brown to gather up all their stuff and drive away in Doc's van, the terrorists don't lift a finger to chastise them or confiscate the remaining plutonium. [There are any number of explanations: 1. The Libyans may have been rendered unconscious in the crash, which while not explosive *did* knock the vehicle to its side and at least one Libyan was unrestrained. 2. The parking lot was the site of machine gun fire and multiple explosions, and the Libyans may have fled the scene before the police arrived.] Corrected by JC Fernandez When back in 1985 Marty's mom asks if this is the night for the big date, Marty answers "How can I go to the lake when the car is wrecked?" His family reacts by going out and checking George's BMW. Seconds later we see that Marty has his own truck - shouldn't they have been checking on that instead? And if it's because he talks about the car (i.e. the BMW) instead of the truck, they should have wondered why he was going to take his fathers BMW up to the lake instead of his truck. [They're probably used to hearing Marty refer to the truck as "the truck," whereas George's car is "the car." Once they heard Marty say the car was wrecked, they didn't have time to think logically and conclude, well, the car may be wrecked but you're taking the truck. More likely they were startled and wanted to go check on the car right away to find out what Marty was talking about.] Even with Marty's brief instructions, it is near impossible that each backing band member (each, and as a whole) could have pulled off a near perfect rendition of Johnny B. Goode, not ever having rehearsed, known or heard the song, etc. [1. It is NOT a perfect rendition. 2. "Near impossible" is not impossible. 3. This posting renders every musical ever made impossible.] In the parking lot when Marty begins to film, Doc says the date and exact time according to his watch. Marty then looks at his watch. Apparently his is off because he shakes his wrist and puts the watch to his ear to see if it is still working. However, he is wearing a digital watch which wouldn't tick or likely have broken parts to rattle. [Character mistake not a movie mistake. I often look at my wrist when asked the time even though I do not wear a watch.] In 1985, when Marty's mum is talking about Jennifer, she mentions that she's never sat in a parked car with a boy before. But as Marty and his mum are sitting in a car in 1955, she says, "It's not like I've never parked with a boy before", which means she has. [Lorraine was obviously lying in 1985 about never being in a parked car with a boy, the same way a parent might lie to their kids about when they lost their virginity if they lost it in high school in hopes of deterring their kids from going out and having sex early themselves.] Corrected by AD In 1985 When Doc is recording himself as he sees the terrorists come with their trucks. Marty is supposed to say, "who, who found you?", or something like that. But as Doc is watching the tape in 1955, Marty never says anything. [Doc stops and rewinds the tape before Marty says anything.] During the first Lou's cafe scene in 1955, Marty asks for a Tab, then a Pepsi-Free, then "something without any sugar in it." Pepsi-Free was "free" of caffene, not sugar (Diet Pepsi was "free" of sugar). Marty knows this because he is seen with both Diet Pepsi and Diet Pepsi-Free in 1985. Of course, had Marty asked for Diet Pepsi in 1955, Lou would not have been able to say "Hey, you want a Pepsi, pal, you're gonna pay for it." [Marty simply changed his order. He was just naming his preferred drinks, not necessarily the ones that don't have sugar.] Corrected by MovieGuy In the scene in the beginning at the mall when Marty is being chased by the Libyans, the tripmeter on the Delorean goes from about 17 miles to 87 miles in a matter of seconds. [The inconsistency of the trip counter has already been submitted.] Corrected by Jazetopher When the wrecked car is being backed into the driveway, it is after dark. But when Marty walks into the house and hears Biff complaining about the blind spot, look out the back glass doors. It's daytime back there. [It is not after dark. It is just getting dark, it is still light outside like a summer evening between 9 and 10pm. Same as in the background when Biff is complaining.]
Near the end when Biff is waxing the BMW, it is close to the garage door. But when the family goes back inside less than a minute elapses and suddenly Biff brings in the book shipment and then gives Marty the keys to the truck. When Marty goes out the front door, the BMW has now suddenly moved to the far side of the driveway. There wasn't time for Biff to finish waxing, accept the book shipment, and move the BMW in less than a minute. [It is never stated that Biff finished waxing the BMW. As for the movement of the car, if he was moving it when the delivery person arrived, all he had to do was get out of the now-moved car, sign a form, and bring in the box. You could do this in a minute.] Corrected by Jazetopher Seeing as Marty changed his future, shouldn't the photo of himself, his brother and sister be different? [Not really. The events of that day, leading up to the picture being taken, could have been the same.] Corrected by Rlvlk The rods of plutonium are transparent red, whereas real plutonium is a silvery metal. [More than likely they would have used a dilute plutonium compound (According to Wikipedia the red colour suggests Plutonium (IV) chloride, rather than pure plutonium metal, which is highly dangerous to handle outside controlled conditions, as it emits enough gamma radiation that would kill Marty and Doc within seconds.] Corrected by Andy Benham When Marty is recovering from being hit by the car, his mom continually refers to him as Calvin. When Marty asks why, she responds "Well thats your name isn't it? Calvin Klein. It's written all over your underwear." But when Marty puts his pants on, we see his purple underwear and there is nothing written on them. [The writing is on the waistband of the underwear which is covered by Marty's shirt. If you watch in slow-mo Marty lifts part of his shirt for a split second and you can see something written on them.] Following the mistake about the menu design in the cafeteria, look at the background. The sun has moved a lot. Look trough the window and you'll notice the shadows were a second before was sunny. [The shadows can easily be explained by passing clouds.]You may also like: Back to the Future Part II | Back to the Future Part III | I Am Legend | Star Wars | Titanic