# Experiment to compare the radiation of heat from different objects.

by crysisfreak69yahoocom (student)

Aim

To observe the energy produced per second depending on the rate of cooling from the objects depending upon the relative ability of its surface to emit energy by radiation of heat.

Hypothesis

The black body has an emissivity of 1 whereas the silver body has an emissivity of 0.1. Emissivity is referred as the ability to emit energy by radiation. Hence the black body will produce more energy. The experiment has to perform with great caution so as the heat radiated by our body does not  interfere with the calculated readings.

Method

• Acquire a clamp stand and fix the thermometer to on it
• Boil water greater , then 85 degrees Celsius and pour the water into a graduating cylinder of volume 250 ml
• After measuring the volume pour the water into anyone of the cylinders depending on which the experiment is performed i.e.  If one is performing experiment on black cylinder pour the water into black cylinder.
• After pouring the water in to the cylinder, adjust the cylinder on the clamp stand such that the thermometer is in the boiling water in the center of the container and touches no surface inside the container.
• At 85 degrees Celsius start the stopwatch and take the temperature readings at equal intervals of time of 20 seconds until 180 seconds
• Perform the experiment 5 times for each of the cylinders

Apparatus needed

• Clamp stand
• Thermometer
• Stopwatch
• Boiling water
• Black cylinder
• Shining cylinder
• Measuring cylinder

Variables

• Temperature of the water boiled from the kettle
• Room temperature  in which the experiment is performed
• Distance at which the thermometer as kept in the water of the container
• Distance between the person performing the experiment and the cans

Controlled variables

• Number of cans
• Amount of water
• Emissivity of cans

Independent variables

• External surface of cans
• Surface area of cans in which the water will occupy the area

Controlling Variables

Temperature of the water – The water in this experiment was used to boil from a simple kitchen kettle and ...