When a nuclear bomb detonates in Central City, Barry, Jesse Quick and Jay Garrick slow down time by entering Flashtime. As everyone in the city is frozen, the three speedsters push themselves to the breaking point to save the city and everyone in it.
Did You Know?
The concept of Flashtime was created for the series. See more
When Barry is in "Flashtime" he is using a pen to write on a glass screen. The pen's ink would simply not flow fast enough to allow him to use it. further to this, he drops the pen and it appears to fall at normal speed, instead of appearing to fall in slow motion as one would expect. Even if the pen had been brought into the flashtime state to allow him to use it (though no suggestion is ever made he can do this with inanimate objects) the pen would have still fallen at the rate determined by gravitational pull (9.81 m/s^2). See more
What do you mean 'we might lose the speed force?'
An explosion of that size would destroy it completely. If that were to happen, every speedster across space and time would lose access to their speed instantly.
Even if it got rid of Thawne and every other evil speedster in the multiverse, you cannot do this, I won't let you.
References Raiders of the Lost Ark