We often have eye fraud. When it is dark for a moment in front of your eyes or the needles of the clock stop for some time, it is called stopped clock illusion. This must have happened to you many times when you suddenly see the clock off and then turned on. This is what psychologists call the stopped clock illusion. University College London has experimented on this.  

In which some people were asked to look aside and suddenly asked to see the time in the digital clock, along with this, their time was also noted. In the meantime, the team noted that the time between watching the volunteers' watch and telling the time was too long, meaning they could see it for a long time. This shows that there is darkness in front of your eyes for less than 1 second.    

Even today many people are surprised how  this thing works. Many people have even failed to solve this mystery. But till now no one has understood how this happens. 

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