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In physics, power is the rate of doing work. It is the amount of energy consumed per unit time. The unit of power is the joule per second (J/s), known as the watt (in honor of James Watt, the eighteenth-century developer of the steam engine). For example, the rate at which a lightbulb transforms electrical energy into heat and light is measured ...
Since the CFL uses only 15 W and not 60 W, the electricity cost will be $7.20/4 = $1.80. The CFL will last 10 times longer than the incandescent, so that the investment cost will be 1/10 of the bulb cost for that time period of use, or 0.1 ($1.50) = $0.15. Therefore, the total cost will be $1.95 for 1000 hours.
Definition. Energy is a conserved quantity that can be accumulated and is transferred as heat, work, and in matter. Modern civilization is possible because people have learned how to change energy from one form to another and then use it to do work. Water Analogy. Energy is like the amount of water a bucket can hold.
2 years ago. 1. power is all about converting whatever your work into the work with 1 second of window. 2. in most cases, you do work for more than 1 sec. thus you have to do divide them by the time it take to do the work. e.g. work_of_pushing_a_box_right = 30J, time = 3s. power = work/time = 30J/3s = 10J/1s = 10W.
- how is P=m.a.v instantaneous velocity?V= instantaneous velocity; Since acceleration and velocity are in the same equation, then the velocity is changing (accelerating) over time, so it...
- How can we measure powerIf you know how much energy is being converted per unit time, that is all you need to calculate power. Ex. measure the current from the battery in...
- In "Can the concept of power help us describe how objects move?", in the last few steps, why is Pavg...Vinitial is 0, therefore it is 1/2Vfinal
- Power can be expressed as P = Work/Change in Time, instead of P = Change in Energy/Change in Time, b...Hello Alex, In general I would agree. In both cases you end up with joules / time. Watch out for context. It seems each field of study has it's own...
- how does finding the area under, of a power vs time graph gives me an average power? shouldn't that ...Area under a power vs. time graph is the equivalent of integrating power with respect to time, which gives work or change in energy. To find averag...
- About the last exercise, the first thing I thought about was 4.17/8 = 0.52, therefore 48% of the tim...This is actually a very good way to think about it. Its good to know equations sometimes, but you just solved a rather tricky problem in a very ele...
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A system possesses energyif it has the ability to do work. Energy is transferred or transformed whenever work is done.. Energy is… 1. a scalar quantity 2. abstract and cannot always be perceived 3. given meaning through calculation 4. a central concept in science Energy can exist in many different forms. All forms of energy are either kinetic or po...
joule English brewer and scientist James Joule(1818–1889) who determined the mechanical equivalent of heat. Multitudinous Atomic and nuclear units
Another scheme 1. solar 1.1. sunshine 1.2. wind 1.3. ocean currents 1.4. ocean thermal temperature gradients 1.5. biomass 1.5.1. food 1.5.2. wood/charcoal 1.5.3. dung 1.6. fossil fuels 1.6.1. coal 1.6.2. petroleum 1.6.3. natural gas 2. everything else 2.1. geothermal 2.2. tidal 2.3. nuclear
Aristotle of Stagira (384–322 BCE) Greece: first use of the word energeia (ενεργεια) in the Nicomachean Ethics. Its contemporary meaning has diverged significantly from Aristotle's original meaning...
Feb 20, 2022 · Furthermore, the typical electric power plant converts only 35 to 40% of its fuel into electricity. The remainder becomes a huge amount of thermal energy that must be dispersed as heat transfer, as rapidly as it is created. A coal-fired power plant may produce 1000 megawatts; 1 megawatt (MW) is \(10^6\) of electric power.
Power. In physics, power is defined as the rate at which work is done. In other words, it measures how quickly energy is being transferred or transformed. Explore the concept of power in physics through an example of two weightlifters, one who lifts faster than the other, to see that power measures the rate at which work is done.
