How much energy was used in doing work on the ball and floor (and in increasing the internal energies of ball and floor)? multiple choice...?
a 1 kg ball is dropped from a height of 2 m and bounces from the floor, rebounding to a maximum height of 1.5 m. During collision, how much energy was used in doing work on the ball and floor (and in increasing the internal energies of ball and floor)? The acceleration due to gravity is 10 m/s^2 a. More than 2.0 J b. Less than 0.5 J but not zero c. 0.5 J d. 1.0 J e. None f. 1.5 J Please show work if you can. This is the one problem on my homework I couldn't wrap my head around :/
What happens to the energy that is used in doing work?
It is converted into other form(s) of energy. For example the work you do if you push something uphill is converted to: - kinetic energy (you make something move) - gravitational potential energy (you increase the height) - heat (friction between object and ground produces heat)
What happens to energy when work is done?
The classic answer is that energy can not be created or destroyed only transformed from one type to another. Personally, I like to view energy as a brick:In each case, energy is being added to the brick. We are adding potential, thermal, and kinetic energy. In each case, work is being performed on the brick. We could say that work is done to increase the energy content of an object.FUN FACT: This and other central concept to work and energy are captured in the Laws of thermodynamics - Wikipedia. The 2nd law implies that perpetual motion machine are not possible. Loosely transmitted, it tells us that a process always looses some heat energy. For example, work is done when we charge a battery. Electrical energy is concerted to chemical energy. Not all of the energy makes the conversion. Some of the electrical energy is turned to heat energy.Regards,APDahlenP.S. Yes, it is redundant to talk about “heat energy.” Heat alone would have been sufficient.
What happens to energy once it has been used?
One has to understand what it means to use energy: using energy means channeling it through the devices of your convenience in order to perform desired action, or to cause a desired effect. For example, you may want to increase temperature in the room. Nothing happens to the energy. It does not change form, since energy has no form. It just flows from one place to the next through the devices of your choosing. If the energy was stored, it gets released. If the energy was moving, it gets stored or retransmitted elsewhere. Using energy means controlling its movement, rather than consuming it. If the movement of energy is controlled, energy causes desired action.
What happens to kinetic energy?
Ever since the invention of the internal combustion engine, scientists and engineers have worked to increase the efficiency of an internal combustion engine. The average internal combustion automobile engine only converts roughly 30-35% of its energy into useful power (which drives your car/truck) rest 65-70% is lost in various points as heat lost + UBHC (un-burned hydrocarbons, responsible for pollutants) + sound energy (noise pollution). One of the major reasons for the loss of efficiency in an engine is the sheer number of parts moving at high speeds. The movement creates great amounts of friction between parts, which uses much of their moving energy to create heat and sound. Lubricants and cooling systems can only do so much about this problem, and since engine operates at very high speed some of your precious air fuel mixture escapes through your car's tail pipe without ignition. So availble chemical energy = actual work done by ic engine to move your car + UBHC (unburned hydrocarbons through tail pipe) + Heat and sound energy 100%energy = 33% work + 33% UBHC+ 33% heat and sound --- (roughly) Now when you hit the break...this 33% of total chemical energy which was converted to work (responsible for kinetic energy of your car, gets converted in to frictional energy and raise the temerature of your break drum and eventually dissipated to environment. Hope this helped Vick
What happens to the work done in stretching a spring?
What happens to the work done in stretching a spring? A). The work goes into increasing the kinetic energy of the spring. B). The work is used up when the spring is stretched. C). The work goes into increasing the elastic potential energy of the spring. D). The work goes into reducing the elastic potential energy of the spring. E). The work goes into increasing the gravitational potential energy of the spring.
When work is done, energy is used. Is it possible that energy can be used without doing any work?
First, I would be cautious about saying that energy is “used”. ‘“Used” implies consumed, and the conservation of energy law states that energy can be neither created or destroyed, but merely transfered into different forms of energy.Now, from an engineering standpoint, energy is the potential to do work. Work is force acting through distance, and shifts the energy that caused the work from one system to another. I hold a rock out the window on the 10th floor. Because I carried it up there, it now has some potential energy. (It has the “potential” to do some work, nothing more). I let it go, and it falls. Some of the PE it had gets transferred to the air, since it is compressing air in front of it s it falls, and this heats the air. Some of the PE is transfered as sound, because if I listen closely, I can hear it falling through the air. It accelerates to the ground, and makes a huge thud. More PE is transfered as sound. When it strikes the pavement, one side of the rock and the pavement under the rock heat up a bit. PE being transfered as heat.You have to remember that as the rock is falling, it is picking up speed, and the total kinetic energy that the rock has just before impact is equal to the PE it had before the drop, less all the parasitic energy transfers that occurred on the way down.I am not going to write a long answer, because in engineering, energy and work are definitions.Can you have energy with no work down? YesCan you have work done and transfer no energy? No
How is work related to energy?
There are different kinds of energy.Light ,heat,electricity , magnetism , electro magnetism , nuclear , chemical and so on.One form of energy that we daily deals with is the mechanical energy . Sound is one form of mechanical energy .Mechanical energy is further classified as mechanical potential energy and kinetic energy .Mechanical energy can be added to a system by the displacement of a force .Whenever a force is displaced through a distance , we say work is done . ( this differs from ordinary usage in life ) Work done on a body means the body gains energy. Work done by a body means the body looses energy .Hence work is change in energy . The mechanical energy is called work, where as heat light , electric magnetic energies are not called as work .Only when a force is displaced we say some mechanical energy is transferred. Hence work and energy are one and the same .
What happens to the potential energy of a weight being lowered?
It reduces. Duh.But the actual question is where does it go.Lowering may also mean free-fall: The potential energy get turned into kinetic energy and maybe heat energy due to air friction.In the case of lowering it slowly, you're doing work against gravity. So the potential energy is converted into heat energy by the movements of the person's body(assuming a normal rope pulley is being used).How do gravitational potential energy and KE work for things being lowered slowly? This page perfectly explains in much detailed terms. Hope it helps :)
Is work done equal to energy?
No. The principles of physics say that while work is performed by different forms energy, work done cannot be equal to the energy used or applied for.For different gadgets/works, different amounts of energy used, in the course of actual application energy wasted/escaped due to friction, misuse, wrong applications, resistance.The amount of energy created by burning of oil, petroleum, CNG, LPG, wood, electricity is never equivalent to the actual works performed.Truly speaking, if it were equivalent to works, there was no questions of unburnt hydrocarbons from the automobiles emission and mills and factories, etc. and air would have never been polluted.Physics further affirmed that even applying 1000 men to work for dragging a train on rail, if the train remains unmoved, NO works, in effect has been performed. But we witnessed those men tried with full forces but to no avail.There are many examples and occasions we experience in our day to day activities and find despite best trials no works done. We often lament for such failures. But in the eyes of Physics. That's the reality.Thanks.