Joule's Experiment Virtual Lab Simulation

General Aim

1- Determine the value of the mechanical equivalent of heat coefficient.
2- Determine the value of coil resistance.

Method

Conversion of electrical energy into heat energy.

Learning Objectives (ILO’s)

• By the end of the experiment, the student should be able to: State the principle of conservation of energy.

• Identify which types of energy were involved in the experiment.

• Recognize how energy conversion takes place from electrical energy into heat energy.

• Identify the different units used to measure energy.

• Determine the value of the mechanical equivalent of heat and the coil resistance.

Theoretical Background/Context

When an electrical current passes through a resistive element (coil), which is completely immersed in water. Electrical energy is dissipated within the element that is transformed into heat energy. This causes the temperature of the element to rise by an amount that is proportional to the time interval, voltage and the current passed through the element. Applying the principle of conservation of energy, we can determine the mechanical equivalent of the heat coefficient and the resistance of the resistive element.

Principle of Work

A certain amount of water is added to a calorimeter of known material and mass. A heater coil is inserted into water that is connected to a power supply, an ammeter, and a voltmeter. Measuring the initial temperature for water. After switching on the power supply electrical energy introduced by the power supply is converted into heat energy that causes the rise in the temperature of water. Waiting 15 minutes and switching off the power supply then watching the thermometer until it reaches the maximum value (final temperature). By some calculations, we get the mechanical equivalent of heat and the coil resistance.