The __________ is the concluding paragraph of Article I Se…

  The __________ is the concluding paragraph of Article I Section VIII of the Constitution — also known as the Necessary and Proper Clause — which provides Congress with the authority to make all laws necessary and proper to carry out its enumerated power.  

A beam of electrons is accelerated from rest through a poten…

A beam of electrons is accelerated from rest through a potential difference of 10 kV before entering a region having uniform electric and magnetic fields that are perpendicular to each other and perpendicular to the direction in which the electron is moving, such that magnetic and electric forces on the electrons point in opposite directions.  If the magnetic field in this region has a value of 0.0039 T, what magnitude of the electric field is required if the particles are to be undeflected as they pass through the region? (me = 9.11