In the original Back to the Future when Marty is trying to get back to 1985, Doc puts an alarm clock on the dashboard of the DeLorean and tells Marty:

"I've calculated the distance and wind resistance retroactive from the moment the lightning strikes. When this alarm goes off you hit the gas."

alarm clock

Moments before the alarm goes off, the DeLorean's engine stops and Marty struggles to get it to start again. While he struggles with it the alarm clock rings. When the engine eventually starts Marty then starts to drive the car and he is successful to travelling back to 1985. Because he started a few seconds late due to the engine trouble, were the Doc's calculations incorrect by a few seconds?

  • Maybe there was a window of opportunity where things would work – BlueMoon93 Mar 20 '17 at 19:24
  • @BlueMoon93 Doc is also quoted saying "So long as you hit the connecting wire with the hook exactly as the lightning strikes the clock tower" – Toby Smith Mar 20 '17 at 19:27
  • 5
    This is one of those things you have to accept on "theatrical faith". If you think about it, there are many things that don't lend themselves to exact calculation: Marty's reflexes from hearing the bell to pressing the gas, how fast and firmly you hit the gas, and there are others. And as you say, the timing has to be exact because the lightning bolt is there for "only a flash". – John Mar 20 '17 at 19:38
  • 1
    Agree with John, I think it is just a case of cinematic realities - when the lighting strikes it perceptibly travels down the wire to electrify the length between the lamp posts - I would imagine that in real life this would have been instantaneous as the speed would have been similar to the speed of light. – Stephen Francis Mar 20 '17 at 20:10

Browse other questions tagged .