Towards a just, equitable, humane and sustainable society

Science - Electricity and Heat


Discoveries of fire and electricity have played a significant role in the development and advancement of our human society. We cannot think of a single day in our lives without heat and electricity. They have become an integral part of our lives. Heat is very important for cooking, drying clothes, keeping ourselves warm etc. Without electricity, most of our appliances like light, fan, grinder, phones, TV would not function. Understanding the phenomena of heat and electricity are integral to be able to come up with innovation that can make our lives more comfortable. In this article, we review a few project ideas in heat and electricity that will help children explore the concepts deeper and relate its application in their day-to-day lives.     

1. What is temperature? How is it measured?

The thermometer is the device that is used to measure temperature. It works on the principle that matter expands on heating. Here is an experiment from the ‘Middle School Chemistry’. In this experiment, students will build a model of their own thermometer using isopropyl alcohol as the liquid.

After students make their own thermometer, an extension of the project can be to research different types of thermometers, the history of thermometers, and how thermometers are made and calibrated.

http://www.middleschoolchemistry.com/lessonplans/chapter1/lesson3

2. Heat in the kitchen

One of the important applications of heat is cooking food. Sometimes, we need to cook on low flame for a longer duration and at other times, we cook on high flame for a short duration. This is also dependent on the vessel in which it is cooked such as mud, aluminium, stainless steel, iron, and ceramics. In this experiment, students will determine which material transfers heat the fastest. Try different kinds of pots to see which type boils water the fastest or use a kitchen thermometer to find out which material delivers the highest temperature after 10 minutes. You can also test and see how long the hot water stays hot in the pot. After doing this project, conclude which pots are most suitable for which kind of dish.

https://www.sciencebuddies.org/science-fair-projects/project-ideas/FoodS...

3. Thermos flask

A thermos flask is used to keep contents hot or cold for a long time. For this, it has to prevent the transfer of heat from the inside to the environment or the other way round. This implies that its design should prevent conduction, convection and radiation. In this project, student teams design insulated bottles with the challenge to determine which materials work best for insulating hot water to keep it warm for as long as possible.

https://www.teachengineering.org/activities/view/ucd_heat_lesson01_activ...

ELECTRICITY

1. Comparing light bulbs in terms of energy consumption and environmental impact

In this activity, students will analyze household electric bills, relating energy consumed, billing rate and cost. At the first stage, they will compare the efficiency of different light bulbs. Then, they will compare the costs of operating a variety of electrical appliances in terms of power ratings, amount of time each appliance is used and the billing rate. At the next stage, the students will measure and compare the energy consumed by the appliances and its efficiencies.

Source: Active Physics – An inquiry-based approach to Physics.

2. How electric currents create magnetic fields- Making a Galvanometer

Italian physiologist Luigi Galvani (1737-1798) is noted for his studies on the effects of electricity on animal nerves and muscles. Galvani accidentally discovered that the leg of a frog twitched when touched with an electrically charged scalpel.

Principles discovered by Galvani and Oersted led to Volta’s invention of the first electric battery. In this experiment, students will build a Galvanometer. A Galvanometer is an instrument for detecting the strength and direction of electrical current.

http://www.energizer.com/science-center/how-to-make-a-galvanometer

Grade: 
8

Term: Term 1

Subject: 
Science