system
Given the following post, respond as if you're commenting on Reddit:
human
What are the differences between Chernobyl, the Tsar Bomba and a modern day nuclear weapon / device in terms of radioactivity?

I'm curious about which would be the most dangerous post explosion. I just finished watching the Netflix show Chernobyl but I'm curious if it was hyped up a little for Hollywood or if its completely realistic, and how it compares to other nuclear events?

Thanks in advanced!
gpt
The whole point of a nuclear bombs is that is uses up as much of its radioactive material as fast as possible to create an explosion (usually only 50% or so). Modern day ones then use this to initiate a fusion reaction which produces far more energy, without any more radioactive fallout. 

These bombs require a minimum of 50kg of highly enriched uranium to produce an explosion (fat man had 64kg). Logically this results in a minimum of 25kg of still actively radioactive material distributed after the explosion.

In Chernobyl, there was well over a tonne of this same radioactive material, producing far far more radiation.

There is a different type of nuke however, called a salted bomb. In these the fission core is surrounded by a material that becomes radioactive when it absorbed a lot of neutrons. Whilst it wouldn't produce the same levels of radiation as Chernobyl, it would be over a much greater area, causing more damage.