A2 Physics Electric Fields

what is electric field

force per unit positive charge

formula for force on a charge in an electric field

F = qE

draw electric field lines

lines that are from positive charges to negative charges

formula for field strength between charged parallel plates

describe the effect of a uniform electric field on the motion of charged particles

parallel to field:

• + charged particle would accelerate in direction of the field

perpendicular to field:

• + charged particle would move to negative plates

• - charged particle would move to positive plates

• conditions -

  • the heavier, the smaller the deflection

  • the bigger charge, the bigger the deflection

  • the faster, the smaller the deflection

what is coulumb’s law

when force is directly proportional to the product of charges and inversely proportional to the square of separation

formula for coulumb’s law

formula for electric field strength due to a point charge in free space

what is electric potential at a point

work done per unit positive charge in bringing a small test charge from infinity to the point

what is electric field at a point equal to

the negative of potential gradient at that point

formula for electric potential in the field due to a point charge

formula of electric potential energy of two point charges