Ask a Teacher

Search



IS THERE FRICTION IN VACUUM?

       Conventional physics holds that in a perfect vacuum, a spinning object would never slow down since there is nothing else to act on it. But according to a new study by Alejandro Manjavacas and F. Javier García de Abajo, this may not be true. 

      The vacuum isn't as entirely devoid of matter as most of us may think. Its only devoid of permanent matter. In a vacuum, tiny temporary particles pop in and out of existence all the time. since these particles pop out on all sides, it hit a spinning object from every direction and hence their cumulative effect should be zero. 
     
      But according to the new discovery, this isn't the case. If a particle hits a spinning object in the direction of its spin, a part of its momentum may be transferred to the object. If, however, a particle hits the object counter to its direction, more of its momentum will be transferred to the object. If particles moving counter to the object's motion hit with more force than the particles moving in the direction of the object, the object will eventually stop moving. 


comments powered by Disqus