Energy Transformation and Power
The lesson covers the process of energy transformation from one form to another, including potential and kinetic energy. It explains the laws of conservation of energy and provides examples of energy conversion, such as mechanical and solar energy. The lesson also defines power and presents its form
- 27:42 “Ehi. Till next time.”
- 09:27 “So, that is transformation of energy from potential energy to kinetic energy. Another example. At what height above the ground, its mass of body, 15 kilogram, be located to have a potential energy equal to kinetic energy...”
- 00:47 “And lastly, six, solve simple problems or nets, energy transformation. Energy transformation is defined at the process of changing energy from one form to another, just like we said earlier on the mechanical energy. We h...”
Energy Sources and Forms
This lesson explains the meaning of energy and identifies its various sources, including solar energy. It describes different forms of energy and how energy is transformed from one form to another. The lesson also covers the implications of using renewable and non-renewable energy.
- 16:12 “For example our blender, the blender in the house, you need electricity to power it and then it gives a mechanical energy by blending the two metals. Electrical energy can be transformed to eat energy. For example you ar...”
- 15:26 “can have water in our flats. Electrical power is used to power on our air condition, our TVs, chemical energy is a source of petrol and it is used by our cars to move from point A to point B. Batteries in reduced convert...”
- 09:41 “forms. Example of these are light energy. Your light. When the light shines, it illuminates everywhere. And if you go close to the bulb, you will notice that you were feeling it. So it can be transformed from light to it...”
Work, Energy and Power
This lesson covers the definitions of work, energy, and power. It includes calculations for work done, gravitational potential energy, and power in watts. The lesson also distinguishes between kinetic and potential energy and explains energy transformation and the law of conservation of energy.
- 10:30 “Take, for example, hot water and cold water. The temperature difference between them, most of the way, you pour hot water or cold water in hot water, the hot water will supply heat to the cold water. So that at the end o...”
- 22:29 “An example, an object of mass 5 kilogram moves with a speed of 10 meter per seconds, calculates the kinetic energy of the object. Now, if our kinetic energy is 1/2 M v square, and from the question, our M equals 5 kilogr...”
- 21:29 “is the potential energy will be converted to the kinetic energy of the body. And kinetic energy is a scalar quantity. If an object of mass M moves with a speed of velocity V, the magnitude of the kinetic energy, which is...”
Work, Energy and Power
This lesson covers the definitions of work, energy, and power. It explains potential and kinetic energy as forms of mechanical energy. The lesson also includes calculations related to work done and the concept of power as the rate of doing work.
- 09:52 “You prove what we call a teen plate. We also have chemical energy. Chemical energies are stored in bones. We have covalent and ionic bones. Now, these kind of energies exist in atomic, molecular or element states. Now, t...”
- 04:52 “And the formula is seen as force times distance. And it is named by a particular man known as James Prescott Joe. James Prescott Joe was a scientist who carried out a lot of research in field of energy and work done. His...”
- 09:04 “It can also be converted into electrical energy, as we see in our source of light, like our solar panel and our inverters we use in our homes. Sound energy, this one works on the principle of wave movement. The wave part...”
Sources of Energy
The lesson covers different sources of energy, including renewable and non-renewable types. It explains how energy is used in society and discusses the environmental impacts of various energy sources. Specific examples include petroleum, natural gas, solar energy, and wind energy.
- 00:02 “Good day, class. My name is Eme Nnamdi John. I'll be taking you on physics, through the topic, energy and society. Now, our first objective today, at the end of the study, Lena should be able to know one, the source of e...”
- 10:10 “Or these are energy that can be replaced. Now, we have energy that can be replaced. After they are being used, we are to replace it back so that it can be able to be used in another form. When these energy are being used...”
- 10:58 “These are the energies that can never be replaced. After they are being used, they can never be replaced again. Now, we have, for example, as nuclear energy, when this one is being replaced in the environment, it can nev...”
Gravitational Force and Fields
The lesson covers the concept of gravitational fields and the laws of gravitational force as proposed by Isaac Newton. It explains the relationship between masses and the distance between them in determining gravitational force.
- 17:43 “we have what's the work done, work done is equal to kinetic energy. Now what is our work done, we have the G M1, M2 over R is equal to kinetic energy, which is one over two MV square, now, I can take care of this M, I ca...”
- 16:52 “the distance, which is R. This can take care of this. By so doing, we have our work done, which give us work done is equal to big G M1, M2 over R, which we produced here. Now, we can say from kinetic energy, from kinetic...”
- 19:24 “for that, to help us impute, okay, let's go, we can get it, alright, from this place, okay, let's say from this we have both, both, the mass of H is equal to G R square over G, now we can impute something into this place...”
Heat and Temperature
This lesson covers the definitions of heat and temperature, their differences, and the effects of heat on substances. It explains the kinetic molecular theory and how heat causes changes in state, such as solid to liquid and liquid to gas.
- 00:48 “Lastly, briefly explain thermal expansivity. Heat energy. Heat energy is a result of movement of tiny particles called atoms, molecules, or ion in solid, liquid, and gas. Heat energy can be transferred from one object to...”
- 21:32 “L1, 10.00, multiplied by 80 minus theta 3. So, we have 0.50, L1, 10, multiplied by 50. So, our linear expansivity for this material equals 1 times the rest of power minus 3 per kV. That is the unit of linear expansivity....”
- 24:02 “1 1 multiplied by 60 minus 30. So, this is a 0.001, multiplied by 250,000 multiplied by 30. So, our change in length, as a result of that temperature difference is 82.5 meter. Evaluation, at the end of the lesson, we are...”
Change of Subject of Formula
This lesson teaches how to change the subject of a formula using the substitution method. It explains the concept of the subject of a formula and provides examples of changing one variable to another. The process involves identifying the current subject and applying inverse operations.
- 07:08 “Oh, I would have plus, A, T minus A, T. So, and taking it out, this takes out this. I'm left with the U. So practically, the U becomes a new subject. So I want to have it as V minus A, T equal to U. U, right hand side on...”
- 03:55 “Let's pick, for example, I want to make, this is the V already at the subject of the formula to really identify from what is given. So I can be given any other equation, but take a note of what's whereby it is given at t...”
- 02:21 “Now these variables are involved. But one is an expression of every other variable, that's the V. So the V, A, is the subject of this entire formula, so the V stands alone. So even if the V is at the right hand side or t...”