Magnetic Fields Flashcards
How are magnetic fields created?
By moving charges.
Rules in determining the direction of a magnetic field. (In solenoid)
- The same side that current goes in is where the field lines go out.
- Right hand grip rule with four fingers in direction of of current.
What is magnetic flux density?
The force experienced per unit length by a long straight carrying unit current and placed at right angles to the field at a point.
Where is magnetic flux density greater ?
Close to the pole of a bar magnet .
Equation of magnetic flux density.
B = F/IL
Unit of magnetic flux density?
Tesla (T)
Define Tesla.
The M.F.D is 1T when a wire carrying a current of 1A placed at right angles to the magnetic field experiences a force of 1N per metre of its length.
Equation for force on conductor.
F = BIL.
The force on the conductor becomes weaker as?
The conductors angle with the magnetic field becomes less than 90⁰.
When two conductors are put beside each other and have current flowing in opposite directions….what is the effect of force on them?
They repel each other. (Opposite happens when the current is in the same direction).
Similarities between magnetic, electric and gravitational fields.
- Action at a distance, between masses,charges or wires carrying current.
- Decreasing strength with distance from the source of the field.
- Representation by field lines.(density of field lines indicates the relative strengths of the field)
Which field is the most significant or strongest for small charge masses and large masses over large distances?
Electric field for small charge masses and gravitational field for large masses at a distance.
