Magnetic flux density (B)
Electromagnetism - OCR A-Level Physics
Key Definition
Magnetic flux density (B)
The force per unit length per unit current on a conductor carrying current at right angles to the field. Measured in tesla (T). 1 T = 1 N A⁻¹ m⁻¹.
The force per unit length per unit current on a conductor carrying current at right angles to the field. Measured in tesla (T). 1 T = 1 N A⁻¹ m⁻¹.
- B is a vectorA quantity with both magnitude and direction (e.g. force, velocity, displacement). quantity - it has direction as well as magnitude.
- Magnetic field lines go from north to south outside a magnet. Inside a solenoid, the field is uniform and parallel to the axis.
- The field around a long straight wire forms concentric circles. Use the right-hand grip ruleCurl the fingers of the right hand in the direction of conventional current; the thumb points in the direction of the magnetic field.: thumb points in currentThe rate of flow of chargeA property of matter that causes it to experience a force in an electromagnetic field. Measured in coulombs (C).. Measured in amperes (A). direction, fingers curl in field direction.
- A flat circular coil produces a field similar to a bar magnet at large distances.