GCSE PHYSICS - MAGNETISM AND ELECTROMAG - LESSON 10 - magnetic field of solenoid 2
Understanding the Magnetic Field of a Solenoid
Introduction to Solenoids
- The lesson focuses on the magnetic field produced by a solenoid, defined as a wire coiled into a spiral.
- A review of previous concepts regarding a straight current-carrying wire is introduced, emphasizing how current direction affects magnetic field orientation.
Magnetic Field of a Single Loop
- A single loop with current flowing out of the paper creates an anti-clockwise magnetic field, while current going into the paper produces a clockwise field.
- Inside the loop, both fields point in the same direction, intensifying the overall magnetic field strength within it.
- Outside the loop, opposing fields weaken each other, resulting in reduced magnetic strength.
Shape and Behavior of Magnetic Fields
- The shape of magnetic field lines changes from concentric circles to ellipses due to varying strengths inside and outside the loop.
- The single loop behaves like a bar magnet with distinct North and South Poles; this behavior is crucial for understanding solenoids.
Adding More Loops: Formation of Solenoids
- Adding more loops increases intensity at the center while decreasing it at the sides, leading to what is known as a coil or solenoid.
- In solenoids, strong and uniform magnetic fields are observed inside due to parallel lines indicating equal intensity.
Characteristics of Electromagnets
- Viewing from one end shows that if current flows clockwise in a solenoid, it generates North and South Poles similar to bar magnets.
- Reversing battery connections alters current flow direction around coils, switching pole positions (North/South).
How to Increase Magnetic Field Strength in a Solenoid?
Understanding Solenoids and Magnetic Fields
- Increasing the magnetic field strength inside a solenoid can be achieved by increasing the number of loops present in the solenoid.