How much energy does a person use in a year? In 2019, total U.S. primary energy consumption per person (or per capita consumption) was about 305 million British thermal units (Btu). In 2018, U.S. per capita energy consumption was about 309 million Btu.

According to the U.S. Energy Information Administration, the average U.S. residential customer uses approximately 909 kWh per month of energy, or around 10,909 kWh per year.

In classical mechanics, kinetic energy (KE) is equal to half of an object’s mass (1/2*m) multiplied by the velocity squared. For example, if a an object with a mass of 10 kg (m = 10 kg) is moving at a velocity of 5 meters per second (v = 5 m/s), the kinetic energy is equal to 125 Joules, or (1/2 * 10 kg) * 5 m/s2.

As every engineer knows, energy calculation is straightforward. The unit of electrical energy is the kilowatt-hour (kWh), found by multiplying the power use (in kilowatts, kW) by the number of hours during which the power is consumed. Multiply that value by the cost per kWh, and you have the total energy cost.

Compute the watts the device consumes daily. Multiply the wattage by the average number of hours the device is used per day. Let’s say you use a 100-watt electric fan for 10 hours per day. Multiplying 100 watts by 10 hours will result in 1,000 watt-hours—that’s how much your electric fan consumes in a day.

Under certain conditions, 10^-18 joules can kill a human. Normally this would be imperceptible. However, if this energy comes in the form of a photon, it is enough to ionize DNA molecules, causing mutations.

Offhand it would seem that a shock of 10,000 volts would be more deadly than 100 volts. But this is not so! While any amount of current over 10 milliamps (0.01 amp) is capable of producing painful to severe shock, currents between 100 and 200 mA (0.1 to 0.2 amp) are lethal.

DC current is about 2-4 times less dangerous than AC current because the AC current will cause faster ventricular fibrillation which is often the cause of death from electric shock. Applying 9V from your hand to hand directly in your bloodstream would then give 30mA DC which is highly unlikely to kill you.

12V*500mA can produce 6w of power enough to kill if it passed trhough your heart, but your body has enough resistance to avoid that happens with little volt. The 500 ma is way more than enough to kill you but 12 volts will not push very much current through your body, not even enough to feel it! So the answer is no.

The minimum current a human can feel depends on the current type (AC or DC) and frequency. A person can feel at least 1 mA of AC at 50-60 Hz, while at least 5 mA for DC. The current may, if it is high enough, cause tissue damage or fibrillation which leads to cardiac arrest.

Body capacitance is the physical property of the human body that has it act as a capacitor. Like any other electrically-conductive object, a human body can store electric charge if insulated.

Dangers of Electrical Shock The amount of internal current a person can withstand and still be able to control the muscles of the arm and hand can be less than 10 milliamperes (milliamps or mA). Currents above 10 mA can paralyze or “freeze” muscles.

Ordinary, household, 120 volts AC electricity is dangerous and it can kill. to flow in a circuit. We can use a simple formula to calculate the current: Current in Amps = Voltage in Volts divided by Resistance in Ohms. Using electrical tools or equipment in wet areas can be a hazard.

While any amount of current over 10 milli- amperes (0.01 amp) is capable of producing painful to severe shock, currents between 100 and 200 milliamperes (0.1 to 0.2 amp) are lethal.

The same article states that high-voltage currents of 500 V and more can cause deep burns, while low-voltage currents consisting of 110–120 V can result in muscle spasms. A person can get an electrical shock through contact with an electrical current from a small household appliance, wall outlet, or extension cord.

An electrical shock may cause burns, or it may leave no visible mark on the skin. In either case, an electrical current passing through the body can cause internal damage, cardiac arrest or other injury. Under certain circumstances, even a small amount of electricity can be fatal.

When you touch a light switch to turn on a light, you may receive a minor electrical shock. You may feel tingling in your hand or arm. Usually, this tingling goes away in a few minutes. If you do not have damage to the skin or other symptoms, there is no reason to worry.

How much electricity does an American home use? In 2019, the average annual electricity consumption for a U.S. residential utility customer was 10,649 kilowatthours (kWh), an average of about 877 kWh per month.

10,909 kWh

Average power per capita was calculated according to the formula: Electric energy per capita [ in watt-hour ] = Total population electricity consumption [ in kW·h/yr ] * 1,000 /population.

China

Efficiency is defined as the ability to produce something with a minimum amount of effort. An example of efficiency is a reduction in the number of workers needed to make a car. The ratio of the effective or useful output to the total input in any system. Efficiency apartment.

Efficiency is defined as the system using the smallest amount of input to produce the highest amount of output. Working efficiently results in a higher produced volume from the same amount of resource input. Tasks and work completed by a team or department are encompassed within the definition of workplace efficiency.

Efficiency is inversely proportional to the time taken to complete a task.

Energy can simply be defined as the ability or capacity to do work. Power is simply the ratio of amount of work done to the time taken/time expended while doing the work.

To calculate the efficiency, divide the standard labor hours by the actual amount of time worked and multiply by 100. The closer the final number is to 100, the more effective your employees are.

Time and Work Formula and Solved Problems

1. The basic formula for solving is: 1/r + 1/s = 1/h.
2. Let us take a case, say a person Hrithik.
3. Let us say that in 1 day Hrithik will do 1/20th of the work and 1 day Dhoni will do 1/30th of the work.

Q 1 – A can do a bit of work in 8 days, which B alone can do in 10 days in how long . In how long both cooperating can do it? A’s 1 day work= 1/8, B`s 1 day work = 1/10 ∴ (A+B) 1 day work = (1/8+1/10) = 9/40 Both cooperating can complete it in 40/9 days.

Solution 1:

1. As 12 men complete the job in 24 days, the work amount is 12×24=288 mandays.
2. For this group of men the total work amount is 288 man days.
3. Thus if 12 men and 12 women work together for a day, it is equivalent to (12+24)=36 men working on the job for 1 day.

1. If the ratio of the speeds of A and B is a : b, then the ratio of the times taken by then to cover the same distance is :1/a : 1/b or b : a.
2. Suppose a man covers a certain distance at x km/hr and an equal distance at y km/hr. Then, the average speed during the whole journey is :- 2xy/(x + y)

To calculate work done in a given time in general if a person A completes a piece of work in a ‘n’ days, then A’s one day work = 1/n. If a man takes 10 days to complete a piece of work, then according to the unitary method work done in one day = 1/10.

A 2018 study also found that it takes job hunters an average of five months to land a new position. During this time, a job seeker will typically edit four versions of their resume, write four cover letters, submit seven applications, and participate in five job interviews.

Working jointly, they can do 1/6 + 1/4 = 2/12 + 3/12 = 5/12 of the total work. So it takes them 1/(5/12) = 12/5 days to finish the job.

They work together for 5 days and the rest of the work is done by C in 2 days. If they get Rs. 450 for the whole work, how should they divide the money? ∴ C alone can do the work in 6×2 = 12 days.