What is the difference between work and power?
Work is defined as the process of energy transfer to the motion of an object through the application of force. Power is defined as the amount of energy transferred in unit time.
What is the work done equation?
Work and energy For example, if a force of 10 newtons (F = 10 N) acts along a point that travels 2 metres (s = 2 m), then W = Fs = (10 N) (2 m) = 20 J. This is approximately the work done lifting a 1 kg object from ground level to over a person’s head against the force of gravity.
What is the equation 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.
How do you calculate efficiency example?
For example, if you put 100 Joules of energy into a machine, and got 50 Joules back out (and the other 50 Joules was wasted by the machine), you would have 50% efficiency. So, if you put in 50 Joules and got 45 Joules back, you would have: % Efficiency = (45 J) / (50 J) * 100% = ?
What are the two equations for efficiency?
Calculating efficiency
- The efficiency of a device, such as a lamp, can be calculated:
- efficiency = useful energy out ÷ total energy in (for a decimal efficiency)
- or.
- efficiency = (useful energy out ÷ total energy in) × 100 (for a percentage efficiency)
How do you calculate cost of efficiency?
Formula. If expenses are $60 and revenue is $80 (perhaps net of interest revenue/expense) the efficiency ratio is 0.75 or 75% (60/80) – meaning that $0.75 are spent for every dollar earned in revenue.
How do you find power?
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.
How do you simplify a power?
To simplify a power of a power, you multiply the exponents, keeping the base the same. For example, (23)5 = 215. For any positive number x and integers a and b: (xa)b= xa· b.
How do you calculate negative powers?
A positive exponent tells us how many times to multiply a base number, and a negative exponent tells us how many times to divide a base number. We can rewrite negative exponents like x⁻ⁿ as 1 / xⁿ. For example, 2⁻⁴ = 1 / (2⁴) = 1/16.
Do I multiply powers?
The exponent “product rule” tells us that, when multiplying two powers that have the same base, you can add the exponents. Adding the exponents is just a short cut! Power Rule. The “power rule” tells us that to raise a power to a power, just multiply the exponents.
How do you divide powers?
To divide exponents (or powers) with the same base, subtract the exponents. Division is the opposite of multiplication, so it makes sense that because you add exponents when multiplying numbers with the same base, you subtract the exponents when dividing numbers with the same base.
How do you multiply powers?
Multiplying exponents with different bases First, multiply the bases together. Then, add the exponent. Instead of adding the two exponents together, keep it the same.