The electrical power of a circuit is equal to the voltage times current. Power is calculated in unit watts, here one watt is equal to ampere into volts. The formula for power is;

Power = current x voltage

Power = I x V

As; V = IR

So, power = I^{2}R

The mechanical power of an object is equal to the ratio of energy to time. In mechanical power, watt is equal to joule per second. The formula for power is;

Power is measured by work done divided by work done \ Power (watts)= work done (j) / time taken (s), where work done is calculated by distance (m) x force (N), and usually the force is the weight of an object.

Hope this is what you inquired for, and good luck with your exam.

Your question is pretty broad. It is hard to tell if you are interested in personal power, political power, the power of money or fame, the Power Of God, or exponents in math.

In math, an exponent, or power, is used as a shorthand way of expressing multiplication. Instead of 10*10*10*10 we can use 10^4 where the power 4 indicates the number of times 10 appears in the product. We can read this as "ten to the fourth power" or "ten to the fourth". Where superscripts are available, this is usually seen as 10^{4}. On Blurtit, the x^{2} tool will turn selected text into a superscript.

There are a number of kinds of problems that require you to "find the power." You run across one of them when you learn to express numbers in scientific notation. You know from your multiplication facts that you can get 1 followed by 2 zeros if you form the product 10*10. So to form the number 1,000,000,000, I could multiply together nine 10s. I can write this number as 1,000,000,000 = 10^9 The power is the number of zeros. If I have 8,300,000,000, I can write this as 8,300,000,000 = 8.3*1,000,000,000 = 8.3*10^9 I can "find the power" by counting the number of zeros there would be if I put zeros everywhere except where the most-significant digit is. In other words, 8,000,000,000 has 9 zeros, so it is written 8*10^9 Equivalently, the 9 tells me how many places to the left I have moved the decimal point in the number.

After you work with exponents a while, you are introduced to logarithms. These are the powers without the base being written. Log[1,000,000,000] = 9, for example. If we all agree on what base we're going to use, we don't need to write it down. For problems in multiplication and division, this can save a lot of work, because it reduces the problem to one of addition or subtraction.

If this doesn't answer the question, give me a shout or ask again more specifically what you want to know.