Power Formula

Most of the things around us require some power for working efficiently. Here, the word power is used to address anything which provides the necessary force or the energy to the thing to work properly. For instance, many devices such as mobile phones, computers, fans, etc work on electricity, if we do not charge the battery of our phone, then it is going to be switched off. Similarly, if there is no electricity in the home, the fan cannot work. Hence, electricity is the power for such devices. Also, this power can be in some other form as well, such as physical, or human resources.

Benefits of Power Formula

The power formula serves many purposes, such as:

• The power formula helps in determining the work done by a particular object or a person at a particular time.

• It helps in determining which object is more efficient and which object is less efficient. For instance, if x and y are doing the same task and x completes in 4 hours, while y completes the same task in 6 hours. It means that the “x” is more efficient than the “y”. It is simply because x has more power than y.

• From the given example it can also be understood how the power can help in determining how much work is done, and at what time it has been done. And with the knowledge of the work efficiency of someone or something, we can also make some good judgments and decisions regarding the same.

A Brief Overview Of The Power Formulas.

• In simple terms, the power of anything can be obtained from dividing the work that the object has done by the time the object has taken to do that work. This is the general idea of power, there are many instances in which the power formula changes.

• There is one formula of the power called “Ohm’s law”, named after the scientist who gave this formula. The formula goes P = VI, and it is given in the electricity chapter of the book. In the formula, P = VI, p stands for power, V stands for potential difference, and I stands for current.

• Ohm’s law also has a variant, which goes like P = r × l2 or V2/ R, this is the formula for the electric power. Here, R is for Resistance, V is for potential difference, and l is for current.

• There is yet another formula, which is called mechanical power equation, or simply power equation. The formula is P = E/t, where P means power, E means energy, and t means time in seconds. This formula states that power is the consumption of energy per unit of time.

There are many more power formulas that you can easily find in the PDF File that Vedantu provides for free.

If we look around ourselves we’ll find several things that require power to run or work. This power can be anything either in the form of electricity, physical, human resources, etc. The main agenda remains the same, which is the ability to do work at a particular time.

The powder formula can be defined as the work done by any specific object or source per given time.

Let’s suppose A and B are two people doing the same task but A finished the task before B then what does it mean?

It simply means that A is more efficient than B and the efficiency is directly proportional to Power hence we can say that A is more powerful than B. This is exactly what power is, it is defined as the work done by a body in the given time.

Power = Work done by the object or body / Total time taken.

Power formula differs as per the required statements, for example, it can be different for force-related objects and also can differ for electronic devices.

The Power Formula for Different Relations and Units are:

P = VI

This formula for power is taken from the electricity chapter. The formula is given by a great scientist named Ohm, and this formula is named after him and is also known as ohm’s law.

This states that power is directly proportional to the potential difference of the conductor. Here P stands for power, V stands for potential difference and I stands for Current. The SI unit is the watt. The unit of V is in volt and for I it’s in the column.

Electric Power Formula

P = R × I2 or V2/ R: These formulas are a variant of ohm’s law. Here R stands for resistance, V stands for potential difference and I stands for current.

It states that power is directly proportional to the square of potential difference and inversely proportional to the resistance offered by the conductor.

 Power Equation

P = E/t: This formula is also called the mechanical power equation. Here E stands for energy in joule and t stands for time in seconds.

This formula states that the consumption of energy per unit of time is called power.

  P = w/t

This is the most common and basic formula of power that we come to know about very early. This formula is derived from the work-energy theorem.

It states that the work done per unit time is called power. Here W stands for work in joule and t stands for time in seconds.

 P = F × s/t

In this formula, F denotes force applied In the object, s denotes displacement of the object and t denotes the total time taken.

It states that the total time taken by an object to displace from one place to another when an external force is applied to it is called power.

The formula of power is different for different fields as mentioned above, but its meaning remains almost the same for all.

NCERT Topic Wise Solutions for all the Classes

Derivation of some power formulae are as below:

Electric Power:

As we know from Ohm’s law:

V = IR

I = V / R

Now putting this value in a standard equation, P = VI

We get,

P = I × I × R

P = I^2 × R

Or,

P = V × V / R

P = V2 / R.  ( hence proved)

Here,

P = Power of the object or body.

V = Potential Difference between two ends of a conductor.

I = current flowing through the circuit.

R = Resistance offered by the wire.

Power Formula

P = F × s/t

As we know,

Power = Work done upon time

P = w/t

Work = Force ( F ) × Displacement(s)

P = F × s/t

Here,

P = Power.

F = Force applied on the body.

W = Work done by the body.

t = Total time taken.

s = Total displacement of the body.

Advantages Of Having Power Formula – Equations With Examples.

• In the subject of science, equations play a vital role, and hence equations must be understood in a better manner. Because only remembering the equations are not going to help the students in better understanding the concept of electricity.

• On the part of examples, it serves as an illustration of the equations. That is to say, with the help of examples the equations can be understood at a deeper level.