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Know The Relation Between Watt and Volt

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Relationship Between Power and Voltage

Let’s suppose that there are two persons viz: P and Q, each of these is allocated a task of data analysis for a limited duration in which they have to fulfill the deadline. A person’s ability will be ascertained by how much time he takes. If person P meets the expectations of their hiring manager, he gets recruited into the company and if he does not, he fails.


So, here person P takes 2 hrs, while person Q takes 3 hrs, so here person P has more power than Q. 


Now, this person has ability but he needs a push, so that push or the driving force is the potential difference. 

 

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Relationship between Watt and Volt

Watt is the SI unit of power while Volt is the SI unit of potential difference. The relationship and differences between Watt and Volt can be understood by carefully examining the differences between Power and Potential Difference. 

In terms of mathematical formulation, 

P = V*I 

Where, P = Power, V = Potential difference, and I = Current flowing between them

The relation between Watt and Volt can be thought of as direct, which means that Watt varies directly with the Volt. This implies the following:

  • When the electric power in terms of Watt increases, there is a corresponding increase in the electric potential in terms of Volt while keeping the electric current constant.

  • However, if the electric power Watts decreases, the electric potential in Volts decreases by the same amount, when the electric current is kept constant.


Difference Between Watt and Volt

How Does Wattage Work?

Watt: An electrical power is measured in Watts. Let’s take our hose analogy.


Imagine you are spraying water from the hose into a bucket. So, here power is the measure of how quickly the bucket is filling up. 


From the Watt and Volt equation, we understand that it is a straightforward concept that power is the product of electric potential measured in volts and the current flowing through the conductor in Amperes. So, the more the wattage, the brighter is the light. 


We might have seen that a 9 W LED bulb is brighter than a 6 W LED bulb. 


Now, talking about voltage:


How Does Voltage Work?

Voltage: A force that makes electricity move is the voltage and it is measured in volts.

Let’s consider a hose analogy:


Imagine that voltage is the pressure in the garden hose, even if the nozzle of the hose is turned off, the pressure still persists inside it. 


So, in relation to the electricity, even if we switch off the bulb (as the bulb is connected across the circuit), the voltage remains in the energized part of the circuit/ckt.


Volt and Watt Difference

Volt is the measure of the potential difference across the ends of the conductor or a conducting terminal of the wire.

Let’s have a look at equation (1):

 P = V * I

1 Watt  = 1 Volt * 1 Ampere

Or,

1 volt = 1 Watt/1 Ampere ....(2)

From eq (2), Watt is the rate at which the electrical work is performed when one ampere of current flows through the conductor on applying the potential difference of one volt across the ends of the conductor.


Now, let’s give a new meaning to the Watt and Volt Relation in terms of AC and DC:


Watt Volt Relation

Type of Current

Formula Used

Terms Used

AC

\[P_{W} = P_{F} * V_{V} * I_{A}\]

\[P_{W}\] = Power measured in Watts

\[P_{F}\] = It is a power factor

\[V_{V} \] = Voltage measured in volts

\[I_{A}\] = Current measured in Amperes

DC 

\[P_{W} = V_{V} * I_{A}\]

\[P_{W}\] = Power measured in Watts

\[V_{V} \] = Voltage measured in volts

\[I_{A}\] = Current measured in Amperes


Watt Related to Volt

The relation between Watt and Volt is direct. It means that Watt varies directly with the Volt. This implies the following things:

  • When the electric power in terms of Watt increases, the electric potential in terms of Voltage increases by the same amount while keeping the electric current constant.

  • However, when the electric power Watts decreases, the electric potential in Volts decreases by the same amount, while keeping the electric current constant.


Let us consider that there are two persons P and Q respectively, each of these is allocated a task of physical labour for a limited duration in which they have to fulfill the deadline. A person’s ability will be judged by how much time he takes. So, if the person P or Q meets the expectations of their hiring manager, he gets recruited into the company and if he does not, he fails.


Now, if person P does the work in 2 hours and Q does the work in 3 hours then we can ascertain that P has more power than Q. So the potential difference is the capacity created between two ends which has an empty space between them and Power is the actual energy that is transmitted between this space per unit of time. 


This is all about watt and volt and their relationship. Understand the definitions and concepts to realize how they are related and grab hold of this topic well.

FAQs on Know The Relation Between Watt and Volt

1. Describe the terms Volt and Watt?

The unit of Power was coined after a renowned Scottish inventor and mechanical engineer named James Watt. In terms of electromagnetism, the watt is the power with which the current flow of one ampere with a voltage of one volt.  While the term ‘volt’ is derived for electric potential, electromotive force, and the electric potential difference. And as Watt and Volt have a direct relationship, which implies that a change in the value of watt will affect the value of volt by the same magnitude.

2. What is horsepower?

In the earlier days, before the invention of the internal combustion engine, most of the travel by people was done on a horse carriage. Hence with the coming of the industrial age and the replacement of horse carriages with motor vehicles, it was felt that there was a requirement to equate the power of the engine with the equivalent power if the engine was replaced with horses. Hence the term horsepower was invented. 1 Horsepower = 746 Watt.

3. What is the significance of Volt and Watt in terms of domestic consumption?

The electric grid has become a central point of the modern lifestyle as every household and industry requires electricity to function. So when electricity is transmitted to our homes, it happens through the instrument of the electric grid that is the electricity is transmitted from the source to the transformer and from the transformer, it is transmitted to our houses. It is interesting to note that the electrical instruments are marked by their usage of Watt and not voltage.

4. What is current?

The flow of electrons in a system from a center of higher potential to a lower potential is known as current. Whenever there is a sufficient difference between the potential of two points and there is a conductive material between them then there is a flow of electrons, this flow of electrons carries energy with them which is directly proportional to the potential difference between the two points. It is also interesting to note that conventionally the flow of electrons is taken to be in opposite direction to the flow of electrons.

5. How many Volts are in a Watt?

When direct current or an alternating current is applied across the electrical circuit or in an alternating current circuit with a purely resistive equivalent load, one watt or W becomes equal to one volt (V) multiplied by one ampere (A), i.e., W = V * I.

6. What is the Power of a Watt?

We define one watt as the energy required by one ampere of current to flow through the conductor on passing the potential difference of one volt through the conductor. The power is the product of the voltage and current, thus for measuring the power in watts, we need both volt and ampere.

7. Describe the terms ‘Watt’ and ‘Volt’.

The unit of Power was named after a renowned Scottish inventor and mechanical engineer named James Watt.


In terms of electromagnetism, the watt is the current flow of one ampere with a voltage of one volt. 


While the term ‘volt’ is a derived unit for electric potential, electromotive force, and electric potential difference. Since watt and volt have a direct relationship, which implies that a change in the value of watt will affect the value of volt by the same magnitude.

8. What is a Volt AMP?

Volt AMP or Volt-Amperes is an apparent power in an electrical circuit that is used in the context of AC circuits only.