Section 3. Fields, Electricity and electromagnetism

Electricity
A catagory that links up many useful applets and shockwave simulation related to electricity.

Kepler's laws
Impact and Gravity Simulator
This is a little java program simulating the interactions of balls. You can grab the balls with your mouse and drag them or throw them. You can control the friction and gravity. You can make the walls be bouncy, or wrap-around. You can simulate planetary systems, rubber balls, Brownian motion, pool table physics, and more.

Kepler's laws of planetary motion
This page provides brief description on the discovery of the Kepler's laws. It has links to three separate pages demonstrating each of the Kepler's laws using both the qualitative and quantitative methods.

Circular, Satellite and Rotational Motion
This gif animation provides several different basic descriptions on the Kepler's laws of Planetary Motion.

Electric Fields E

Electric potential V
Electric Charges
This applet allows us to see in a graphical way concepts like electric and potential fields.
In this program, the players can move, erase or place an static charge. The amount of charge can also be adjusted. Besides, the players can also choose different form of the animation display.

Charging and discharging of capacitors

Current electricity
Kirchhoff's Rules (Circuit 1)
Kirchhoff's Rules (Circuit 2)
Kirchhoff's Rules (Circuit 3)
Kirchhoff's Rules (Circuit 4)
Kirchhoff's Rules (Circuit 5)

Resistance, Ohm's law, Resistivity, Variation of resistance with temperatures
OHMS LAW: Activate the Light Bulb
This java applet examines the Ohm's law by a light bulb circuit. The animation provides a  light bulb with fixed ampere value and it allows the players to change the value of the voltage supply. After the voltage is chosen, the students are required to add the resistances to the circuit in order for the light bulb to glow. The basic theory of the dc circuit is also provided.

Ohm's law
This simulation shows the current  in a circuit. After entering the value of voltage supply, the resistance of the circuit and the bulb, the power dissipated and the current in the circuit are calculated. Quantitative and the qualitative treatments are shown  and a quiz with solutions are provided.

Measure voltage and current in a Wheatstone Bridge
The Wheatstone Bridge is used to determine the unknown resistance in a circuit by adjusting a known resistance. This java applet demonstrates how the Wheatstone Bridge works and the players can measure voltage and current at any places in the circuit. It also allows the user to enter the values of the resistance and calculate the unknown resistance with the answer checked by the progamme.

Electromagnetism, force on current carrying conductor, magnetic field

Force on a moving charge in a magnetic field. Measurement of magnetic fields.
Charged Particles Moving in a Magnetic Field

B-field around long straight wire, inside long solenoid, carrying current
Biot-Savart Law
This page provides the description of the Biot-Savart Law and using a java applet program to demonstrate the relationship between the magnetic field and the current.

Series combination of L,C,R, impedance

Analogue system, amplification, feedback using operational amplifier

Operational amplifier