Q.What is Hall Effect?
A.When a current carrying conductor is placed in a magnetic field mutually perpendicular to the direction of current a potential difference is developed at right angle to both the magnetic and electric field.This phenomenon is called Hall effect.
Q.Define hall co-efficient.
A.It is numerically equal to Hall electric field induced in the specimen crystal by unit current when it is placed perpendicular in a magnetic field of 1 weber/(meter*meter).
A.It is the ratio of average drift velocity of charge carriers to applied electric field.
Q.Why is Hall potential developed?
A.When a current carrying conductor is placed in a transverse magnetic field the magnetic field exerts a deflecting force(Lorentz Force) in the direction perpendicular to both magnetic field and drift velocity this causes charges to shift from one surface to another thus creating a potential difference.
Q.What is Fleming’s Left Hand Rule?
A.Stretch thumb,first finger,middle finger at right angles to each other such that fore finger points in the direction of magnetic field,middle finger in the direction of current then thumb will point in the direction of the force acting on it.
Q.How does mobility depend on electrical conductivity?
A.It is directly proportional to conductivity.
Q.Define Hall angle.
A.It is the angle made with the x direction by the drift velocity of charge carrier is known as hall angle.
Q.Which type of charge has greater mobility?
A.In semiconductors,electron has greater mobility than holes.
Q.What happens to the hall coefficient when number of charge carriers is decreased?
A.Hall coefficient increases with decrease in number of charge carriers per unit volume.
Q.Name one practical use.
A.It is used to verify if a substance is a semiconductor,conductor or insulator.Nature of charge carriers can be measured.
Read about semiconductors too.