Chapter 13: Electromagnetism Flashcards
Electromagnetism, Fleming's Left Hand Rule
What happens when a conductor carries a current?
A circular magnetic field is created around it
What happens if a magnetical material is placed near a conductor carrying current?
The magnetic material will be attracted to the conductor
Why does the conductor experience a resultant force when a current is passed through it
When a current is passed through a conductor, the circular magnetic field created around it is not uniform. Therefore, the conductor will experience a resultant force in the direction of the weaker magnetic field
Why is a magnetic field created around a current carrying conductor?
A conductor consists of a large amount of free electrons. When a current is passed through it, the electrons start drifting in a fixed direction. The individual electrons will start feeling a magnetic force in the same direction, which causes the conductor itself to experience a magnetic force
At what angle are the directions of the force, current and magnetic field in a conductor related to each other?
They are perpendicular to each other
What are some factors that affect the strength of the force experienced by a current carrying conductor?
Strength of the magnet (As strength of magnet increases, strength of force increases)
Strength of the current (As strength of current increases, strength of force increases)
Number of coils (As number of coils increases, strength of force increases)
Area of the coil (As area of coils increases, strength of force increases)
Winding the coils directly on the soft iron core (If coils are directly on the iron core, the magnetic field lines become more concentrated)
Why do two parallel conductors repel if their current flows in the opposite direction?
As predicted in right hand grip rule, the direction of the two magnetic fields will push against each other, which will cause them to repel against each other
What is the purpose of Fleming’s Left hand rule?
To predict the direction of motion of current carrying conductor, direction of current in condcutor, or direction of magnetic field around current carrying conductor
What do the three fingers in Fleming’s Left Hand Rule represent?
Thumb: Direction of Motion
Index: Direction of Magnetic Field
Middle: Direction of Current
