fields and forces Flashcards
field
region where a force is experienced by a particle possessing the relevant property
field strength
the force acting per unit charge/mass, it is a vector
field/flux lines
direction can be shown along with magnitude shown by the width of the lines
Newton’s universal law of gravitation
every particle in the universe exerts an attractive force on every other particle. The magnitude of the force can be seen through F=G(m1m2/r^2)
G is the universal gravitational constant that is the same anywhere in the universe
particles that are separated by more than their radii can be treated as point masses (middle of the mass)
gravitational field strength
the gravitational force per unit mass or the gravitational flux per unit area. the direction= the direction a unit point mass would move
SI=Nkg^-1or Nms^-1
gravitational field strength at the surface of the planet
F=G(M/r^2) where M is the mass of the planet.
the field are radial pointing towards the planet
law of conservation of electric charge
the net charge of an isolated system remains constant
Coulomb’s law
two charges at a distance r exerts a force on each other in line between them with a magnitude of F=k(q1q2/r^2) or F=q1q2/4πε0r^2
electric field strength
the electric force per unit charge or the electric flux per unit area. direction= direction a unit positive charge would move
SI=N per Coulomb
magnetic north/ south
direction of the current points north
magnetic field magnitude (strength
the magnitude flux per unit area
SI=Nm^-1A^-1=tesla
direction= direction a North pole would move (right hand grip rule)
magnitude of the force on a charge moving in a magnetic field
F=qvBsinΘ
B magnitude of magnetic field
v velocity of charge
Magnitude of force on a current-carrying conductor in a magnetic field
F=BILsinΘ
B magnitude of current
Flemming’s left hand rule
for direction of the force on a charge/current in a magnetic field
THumb direction of force/THurst
SeCond finger is Current
First finger is direction of magnetic field
Uniform field
Constant strength; field lines parallel and equidistant for each other.
