Electromagnet Explorer
Build your own electromagnet by wrapping copper wire around an iron nail and connecting it to a battery. Observe how the magnetic field appears when current flows and how it can attract paper clips. Adjust the number of coils and current to see how it affects the magnet's strength.
When the circuit is closed (switch ON), the nail becomes magnetized and attracts paper clips. The strength depends on the number of coils and battery voltage.
Coils: 15 turns
Voltage: 1.5V
Magnetic Field: OFF
The Science Behind Electromagnets
Electromagnets demonstrate the relationship between electricity and magnetism:
- Electromagnetism: Electric current creates a magnetic field (Oersted's discovery).
- Solenoid: Coiling the wire concentrates the magnetic field along the axis.
- Core material: Iron nail becomes magnetized (ferromagnetic material) amplifying the field.
- Right-hand rule: Thumb points to north pole when fingers curl in current direction.
- Strength depends on: number of turns, current magnitude, and core material.
The magnetic field strength (B) of a solenoid is given by:
B = μ₀μᵣnI
Where:
μ₀ = permeability of free space (4π×10⁻⁷ N/A²)
μᵣ = relative permeability of core material (~200-5000 for iron)
n = number of turns per unit length
I = current in amperes
