- Power: P = W/T.
- Work: W = P*T.
- Time: T = W/P.
- Where, P = Power, W = Work, T = Time.
How do you calculate work energy and power?
- work done = force × distance moved in direction of force.
- change in gravitational energy = mgh.
- power = work donetime taken, power = rate of energy transfer.
- power = force × velocity.
- efficiency = useful energy transferredtotal work done × 100 %
The point is that
for the same amount of work, power and time are inversely proportional
. The power equation suggests that a more powerful engine can do the same amount of work in less time. … That is, some people are capable of doing the same amount of work in less time or more work in the same amount of time.
What are the 3 equations for power?
We now have three equations for electrical power, with two derived from the first using the Ohm’s law equation. These equations are often used in problems involving the computation of power from known values of electric potential difference (ΔV), current (I), and resistance (R).
What is the formula for work with time?
Work Done =
Time Taken × Rate of Work
.
Rate of Work = 1 / Time Taken
. Time Taken = 1 / Rate of Work. If a piece of work is done in x number of days, then the work done in one day = 1/x.
How is power calculated?
Power is a measure of the amount of work that can be done in a given amount of time.
Power equals work (J) divided by time (s)
. The SI unit for power is the watt (W), which equals 1 joule of work per second (J/s). Power may be measured in a unit called the horsepower.
What is the formula for efficiency?
Efficiency is often measured as the ratio of useful output to total input, which can be expressed with the mathematical formula
r=P/C
, where P is the amount of useful output (“product”) produced per the amount C (“cost”) of resources consumed.
What is work done formula?
Work, in physics, measure of energy transfer that occurs when an object is moved over a distance by an external force at least part of which is applied in the direction of the displacement. … If the force is being exerted at an angle θ to the displacement, the work done is
W = fd cos θ.
What is the formula for work and power?
Criteria Work | Formula Total Work Done (W) = Power (P) x Time (t) or Work = Displacement x Force | Measurement Unit (SI unit) The standard unit of work is the Joule denoted as (J). Furthermore, you can measure work in electron volt (eV), kWh, GWh, and MWh |
---|
What is current formula?
The current is the ratio of the potential difference and the resistance. It is represented as (I). The current formula is given as
I = V/R
. The SI unit of current is Ampere (Amp).
What is power multiplied by time?
Energy
, with units of joules (or watt-seconds), is power multiplied by time.
What is power measured in?
Electricity is measured in units of power called
Watts
, named to honor James Watt, the inventor of the steam engine. A Watt is the unit of electrical power equal to one ampere under the pressure of one volt. One Watt is a small amount of power.
What is the difference between work and power?
Work is referred to as the process of energy that is transferred to an object’s motion by applying force. It is generally represented as the product of displacement and force. Power is the amount of energy that is transferred in a unit of time. The formula for calculating the force is
Work = Force * Displacement
.
What is the formula for calculating energy efficiency?
Energy efficiency is calculated
by dividing the energy obtained (useful energy or energy output) by the initial energy (energy input)
. For example, a refrigerator has an energy efficiency of 20 to 50%, an incandescent bulb about 5%, a LED lamp over 30%, and a wind turbine 59% at most.
What are examples of efficiency?
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.
What is a good efficiency ratio?
An efficiency ratio of
50% or under
is considered optimal. If the efficiency ratio increases, it means a bank’s expenses are increasing or its revenues are decreasing. … This means the company’s operations became more efficient, increasing its assets by $80 million for the quarter.