Energy – Hub of related Posts

Solar energy is converted into electricity using photovoltaic (PV) cells or concentrating solar power plants. Photovoltaic cells convert sunlight directly into electricity. solar energy for home Individual photovoltaic (PV) cells are combined in modules of about 40 cells to form a solar panel; 10 to 20 solar panels are used to power a typical home. The panels are usually mounted ...
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Let's see how Fishing rod acts as a specific class of lever, and why it is used. When we use a fishing rod to cast a line, the rod works as a class 3 lever. Fulcrum and load are at 2 opposite ends of the fishing rod. Fishing rod as a lever Effort (force) is applied in between fulcrum and ...
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Crowbar - One of the simplest kinds of lever is the crowbar, which is a class 1 lever. Crowbar as a lever We use a crowbar to lift very heavy objects off the ground. The fulcrum of the crowbar is in between the effort and the load. The distance between fulcrum and effort(force applied) is called the effort arm, and ...
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All three classes of levers make work easier, but they do so in different ways. In this post, we will discuss a few distinguishing pointers of three types of levers. And, these pointers will help to compare three classes of levers structurally and functionally. Compare levers belonging to three classes – In a first-class lever, the fulcrum resides between load ...
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Some of the machines you use every day are made up of several simple machines. Two or more simple machines that operate together form a compound machine. Look at the can opener in Figure 1. figure 1: can opener as a compound machine Compound machine - a can opener To open the can, you first squeeze the handles together. The ...
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A gear is a wheel and axle with the wheel having teeth around its rim. When the teeth of two gears interlock, the turning of one gear causes the other gear to turn. figure 1: gears features of a gear When two gears of different sizes are interlocked, they rotate at different rates. Each rotation of the larger gear causes ...
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In this post, we will discuss three types of pulleys, and how they operate, and how they differ in their operation and utilities. The types we will discuss are (1) Fixed Pulleys, (2) Movable Pulleys, (3) the Block and Tackle. Fixed Pulleys A fixed pulley, such as the one in Figure 1, is attached to something that doesn’t move, such ...
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In this post, we will briefly mention the equations valid for elastic collisions. We can use these equations to solve numerical problems related to elastic collisions. The Equation for the conservation of momentum (for elastic collision) Now, to solve problems involving one-dimensional elastic collisions between two objects, we can use the equation for the conservation of momentum. First, the equation ...
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The image below shows a list of equations and formulae from the chapter "Energy" of the GCSE Physics syllabus. This is also helpful for all other equivalent boards like CBSE, ISC, ICSE. Equations to learn from Energy chapter of physics syllabus Equations to learn from Energy chapter of physics syllabus ...
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In this post, we will first find out what the efficiency of a machine means, and then we will solve numerical problems using the concept and formula of the efficiency of machines. If a machine, such as an electric motor, is used to raise a load, electrical energy must be provided to the motor. This is the input energy to ...
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In this post, we will draw different types of Potential Energy Diagrams. Each of these diagrams is based on a specific equation of potential energy. For elementary courses and the College Board exams, the most important types of potential energy are gravitational potential energy and spring potential energy, also known as “harmonic oscillator potential energy.” Potential Energy Equations 1 ) ...
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Energy is defined as the capacity to do work. The various forms of energy can be classified as:• Mechanical (kinetic and potential)• Heat• Radiant (electromagnetic)• Chemical (potential)• Sound• Electrical/magnetic• Nuclear In the following sections, we will discuss each of the above-mentioned forms of energy. Mechanical energy Mechanical energy includes both kinetic and potential energy. Friction is related to mechanical energy ...
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In this post, we will derive the equation of the total energy of an orbiting body, and then will solve a numerical problem using the formula derived. Derive the formula of the total energy of an orbiting body (or satellite) To calculate the total energy of an orbiting body (say a satellite) we have to find out the sum of ...
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In this post, we will briefly discuss the science behind the operating principle of the microwave oven. This marvelous invention somehow heats only the soft parts of the food and leaves the inorganic and hard materials, like ceramic and the surfaces of bone, at approximately the same temperature. A neat trick, indeed, but how is it done? Let's see how ...
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In this post, we will solve a few interesting numerical problems based on specific heat capacity. Learn more about Specific heat capacity here. Solving numerical problems using specific heat capacity formula Question 1] A tank holding 30 kg of water is heated by a 3 kW electric immersion heater. If the specific heat capacity of water is 4200 J/(kg ºC), ...
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Here, we will see how the Load-extension graph of a body can help us to calculate the energy stored in a deformed material. We will take two Load-extension graphs for this. Energy stored in a deformed material that obeys Hooke's law The first load-extension graph (figure 1a) belongs to a body that obeys Hooke's law, i.e., extension is proportional to ...
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Let's discuss the application of forces to change the shape of an object and the concept of elasticity related to this shape change. We will cover the stretching of spring as a case study. If one force only is applied to an object then the object will change speed or direction. If we want to change the shape of an ...
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In this post, we will discuss how the conservation of energy is maintained in levers and other machines. A machine is a device used to multiply forces or simply to change the direction of forces. The concept that underlies every machine is the conservation of energy. A machine cannot put out more energy than is put into it. A machine ...
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A pulley is a grooved wheel with a rope, chain, or cable running along the groove. A pulley can change the direction of the input force or increase the output force, depending on whether the pulley is fixed or movable. A system of pulleys can change the direction of the input force and make the output force larger. In this ...
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In some situations, the use of conservation of energy can be a much simpler method to solve projectile motion problems than using the kinematics equations. Solving projectile motion problems makes use of the fact that Ek + Ep = constant at every point in the object’s flight (assuming no loss of energy due to friction). In other words, at each ...
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In this post, we will discuss how transfers between kinetic energy and potential energy happen in a simple pendulum. We will also discuss Energy Conservation in a Simple Pendulum. Finally, we will derive the equation for the maximum speed of the pendulum bob. How Transfer between KE and PE happens in a simple pendulum? A simple pendulum is an excellent ...
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Energy is transferred or transformed from one energy form to another via an energy pathway. In this post, we will briefly discuss the following topics: (a) different forms of energy (b) different mechanisms of energy transformation or conversion or transfer (c) Numerical problems related to energy conversion or transformation with the solution. Here let's quickly revise some fundamentals related to ...
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Let's find out some important one-liner definitions from the work-energy-machine chapter in physics. work, energy, simple machine - definitions What is a complex machine? a machine that combines two or more simple machines define efficiency Efficiency is output work divided by input work What is energy? the ability to do work What is gravitational potential energy? energy acquired by doing ...
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Of all simple machines, the mechanical advantage is easiest to calculate for pulleys. To find out the mechanical advantage of a Pulley, simply count the number of ropes supporting the load. That is the IMA or Ideal Mechanical Advantage of Pulley. Once again we have to exert force over a longer distance to multiply force. To raise a load 1 meter ...
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Here we enlist important key equations from the Work, Energy, Power & Simple Machines chapter. Equations related to Work, Power and the Work-Energy Theorem Let’s examine how doing work on an object changes the object’s energy. We will use cases related to a piece of rock to apply different equations from work & energy. Equation for work[Work is the application ...
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The screw shown in the Figure is actually a lever attached to a circular inclined plane. The lever part of these screws is a screwdriver. The distance between screw threads is called pitch and has the symbol P. L is the radius of the screw head surface. The effort is applied at the screw head surface with a turning effect ...
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This Gravity and Mechanical energy Notes [PDF] is primarily for the 10th grade physics syllabus of different international boards. This also covers the class 10 physics syllabus on Gravity and Mechanical energy for boards like ICSE, CBSE, etc. This physics class note covers the theoretical as well as the numerical part of this important chapter. We hope, the students appearing ...
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This Work-Energy-Power Notes [PDF download] is primarily for the grade 12 or 12th-grade syllabus of different international boards. This also covers the class 11 physics syllabus on work, energy, and power for boards like ICSE, CBSE, etc. This physics class note covers the theoretical as well as the numerical part of this important chapter. We hope, the students appearing for ...
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figure 1: Mechanical Advantage of a Wedge - formula A wedge is a simple tool in the shape of a triangle. In other words, a wedge is simply two inclined planes back to back.  Figure 1 shows the simple formulas for calculating the IMAs of these machines. The mechanical advantage formula for a wedge is dependent on its geometry: MA of a ...
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When we hear the word machine, images of power tools or construction equipment come into our minds. While these are certainly some examples of machines, devices as simple as hammers and screws are also machines. Why are simple tools like hammers and screws considered to be machines? Because like all machines, they also change forces and make work easier. What ...
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This post focuses on the Derivation of Gravitational potential energy equations when the reference varies from the planet's surface to infinity. Gravitational potential energy, Ep, is the energy of a mass due to its position within a gravitational field. This energy can be released (and converted into kinetic energy) when the body is allowed to fall.In this post, let's find ...
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The Law of conservation of energy states that the total energy of an isolated system remains constant. Now in this post, we will discuss this in detail, write its statement, and then derive an equation expressing this law of conservation of energy. So let's begin. Law of Conservation of Energy - Explanation As per the work-energy equation the total energy ...
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The SI unit of energy joule is too large a unit of energy for the microscopic world. A more convenient unit of energy for the microscopic world is the electronvolt, eV. eV by the way is not part of the SI system. What is electronvolt? | Define electronvolt We define the electronvolt as the work done when a charge equal ...
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Mechanical Advantage of Wheel and Axle Mechanical Advantage of Wheel and Axle = M.A = Radius of the wheel/radius of the axle = R/r. As R > r, the MA of wheel and axle is always greater than 1. Wheel and axle is actually a form of lever. The difference is that the effort arm can rotate in a complete ...
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Here we will obtain or derive an expression for the potential energy of elastic stretched spring. This energy is also known as elastic potential energy. To get this equation, we'll calculate the work done to stretch or compress a spring that obeys Hooke’s law. Hooke’s law states that the magnitude of force F on the spring and the resulting deformation ...
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The energy possessed by a moving body due to its motion is known as Kinetic Energy. Here we will derive the translational kinetic energy equation which goes like this: K = (1/2) mV2. So let's BEGIN. How to derive the equation of Kinetic Energy? | Derive Translational KE equation Let's take an object of mass m which is at rest ...
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The relation between momentum(p) and kinetic energy(K) of an object of mass m can be expressed with this equation: p = (2mK)(1/2)That means the square root of 2mK gives us the momentum value. Now let's derive the equation that gives the relationship between momentum and kinetic energy. Derive an equation to show the relationship between momentum and kinetic energy | ...
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Work-Kinetic Energy Theorem with derivation: In this post, we will discuss the special relationship between work done on an object and the resulting kinetic energy of the object and come up with the statement of the work-kinetic energy theorem. We will also see how to derive the equation of the work-kinetic energy theorem.Everyday experience supports this theorem. If we see ...
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A sign with a vector quantity denotes direction. But, Work is a scalar quantity. So a negative sign with it (i.e. a negative work) has no connection with its direction. Then what is negative work? When work done by an external force on a mass reduces the energy of that mass then we say that the work done is negative ...
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Ideal Mechanical Advantage (I.M.A.) - The ratio of the total load to the effort is called Ideal Mechanical Advantage (I.M.A.) Therefore, I.M.A. =Total load/effort. [ the total load is the sum of the force to overcome the moveable parts, load due to friction, and the useful load.]Actual Mechanical Advantage (A.M.A.) - The ratio of useful load to the effort is ...
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Standing on toes acts as a second class lever (also known as class II or type 2 lever). This is an example of the presence of a lever mechanism in the human body.The foot acting as a lever arm with calf muscle supplying an upward effort, the weight of the body acting as a downward load, and the ball of ...
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The nodding of the head acts as a first-class lever (also known as class I or type 1 lever). In this lever, the skull acts as the lever arm. Pivot is the place where our skull meets the top of our spine. And the neck muscles at the back of the skull provide the force (effort) to lift our head ...
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If the mechanical advantage of a lever is more than 1, a lever can act as a Force Multiplier. That means using that lever more load can be overcome by applying less amount of effort. Example, Crowbar, Bottle opener, nutcracker If the mechanical advantage of a lever is less than 1, a lever can act as a speed Multiplier. That ...
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Explain why scissors for cutting cloth may have blades longer than handles, but shears for cutting metals have short blades and long handles. - to explain this we need a comparison of Scissors & shears with their mechanical advantage.Scissors and shears apparently may look identical. Both of them belong to the class I lever, having the fulcrum in between load ...
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What is the Work done by Gravity on an object having Horizontal circular motion? Is it positive, negative, or zero work?We will set up a quick experiment for easy observation. How to set up an experiment to find out work done by gravity on a horizontally circulating object? Let’s tie a piece of stone to one end of a string ...
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The mechanical advantage of an inclined plane is calculated as the ratio of the length of the incline and the height of the incline. It can also be calculated using the value of 1/(sin θ), where θ is the angle of inclination.An inclined plane is a simple machine that makes our life easier. All sloping, paved surfaces for walking or ...
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What Is Potential Energy?Potential energy is a form of stored energy - it is the energy possessed by a body at rest due to its position or size or shape. By doing work, forces act to increase and decrease the kinetic energy of objects within a system. If the kinetic energy that’s removed can be stored and recovered later, the ...
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In this post, we will discuss the forces acting on a mass sliding down an inclined plane. To do this we will take the help of the concepts of Vector Resolution. Here we are not considering the presence of friction. Forces acting on a mass sliding down an inclined plane The first step when setting up the problem is to ...
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A 10 kg ball is dropped from a height of 10 m. Find (a) the initial potential energy of the ball, (b) the kinetic energy just before it reaches the ground, and (c) the speed just before it reaches the ground. (a) The initial PE = mgh = 10. 9.8 . 10 = 980 J (b) The KE just before ...
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This post is focused on Numerical Problems on Work, Energy, Power with solutions, and a problem worksheet for you. This is very useful for high school students studying Physics, more precisely for class 10 students of ICSE, CBSE, international boards like IGCSE, state boards, etc.) Numerical Problems on Work, Energy, Power | class 10 ICSE, CBSE | solved i] Find ...
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In this post, we will find out the equation of Efficiency that relates mechanical advantage and velocity ratio of an ideal machine. Equation of Efficiency that relates mechanical advantage and velocity ratio of an ideal machine The efficiency of a machine = Work output / Work input .... (1)Now, Work output = Load x displacement of the load ..... (2)And ...
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Here you will find Numerical Problems on Lever's mechanical advantage & velocity ratio. Try to solve and if required refer to the solutions given. We will continuously add newer problems. Numerical Problems on Lever's mechanical advantage & velocity ratio 1 ) Calculate the mechanical advantage of a class 2 lever such that the length of the rod is 2 meter ...
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The Velocity Ratio of a machine and the Velocity Ratio Formula are the topics of this physics article. Also, we will see how the value of the Velocity Ratio varies in the case of speed multiplier machines and Force multiplier machines. Velocity Ratio | Definition of Velocity Ratio The velocity ratio of a machine is defined as the ratio of ...
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Power is the rate at which work is done or the rate at which energy is supplied or used. Like work and energy, power is also a scalar quantity.The SI unit for power is Joules per second (Js-1), which is defined to be a Watt (W). So 1 W = 1 J/s. There are other popular units like Kilowatt and ...
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Types of levers - Levers are classified according to the relative positions of fulcrum, load, and effort points in the lever body. We will discuss different types of levers with examples in this post. So, let's start. How many types of levers are available? On the basis of the location of fulcrum, load, and effort in the lever body, levers ...
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In this post, we will talk about the Mechanical advantage formula (MA formula) for different simple machines. Mechanical advantage Formula | MA formula The Mechanical advantage formula (MA formula) can be written as follows: (1) Mechanical Advantage MA = output force/input force (2) Mechanical Advantage MA = resistance force/effort force. The machine uses this resistance force to lift or pull ...
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In this post we will discuss different aspects of freefall physics. Here, we will find out (a) how to find the weight of a freely falling body (b) How the velocity of a freely falling body changes every second if we ignore air drag force (air resistance)? (c) Why do we feel weightless during freefall (d) Kinetic energy of a ...
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Work done by a force - In Physics Work is done by a force only if the object on which the force is applied makes a displacement. Without this displacement, work done is zero irrespective of the force applied. Work done by a force depends on the 3 parameters: (a) the force applied (b) The displacement and (c) The angle ...
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MA of a lever & its formula The mechanical advantage of a lever is the ratio of the load the lever overcomes and the effort a person or system applies to the lever to overcome some load or resistance. In simple words and as per the formula, it's the ratio of load and effort. The formula of the mechanical advantage(MA) of ...
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