Umair Gaines
The joule is the unit of energy in the International System of Units (SI). One joule is equal to the work done by a force of one newton acting through one metre. In electrical terms, the joule is equivalent to one watt-second, which is the energy released in one second by a current of one ampere through a resistance of one ohm. This is also equal to the work required to move an electric charge of one coulomb through an electrical potential difference of one volt.
| Characteristics | Values |
|---|---|
| Unit of energy in the International System of Units (SI) | 1 J = 1 kg⋅m2⋅s−2 |
| Work done when a force of one newton displaces a body through a distance of one metre | 1 newton x 1 metre |
| Energy dissipated as heat when an electric current of one ampere passes through a resistance of one ohm for one second | 1 ampere x 1 ohm x 1 second |
| Energy required to move an electric charge of one coulomb through an electrical potential difference of one volt | 1 coulomb x 1 volt |
| Work required to produce one watt of power for one second | 1 watt x 1 second |
| KiloJoule (kJ) | 1,000 Joules |
| MegaJoule (MJ) | 1,000,000 Joules |
| Watt-second | 1 watt x 1 second |
Explore related products
What You'll Learn
One watt-second is equivalent to one joule
The joule is the unit of energy in the International System of Units (SI). It is defined as the work done when a force of one newton moves an object a distance of one metre in the direction of that force. It is also the amount of energy dissipated as heat when an electric current of one ampere passes through a resistance of one ohm for one second.
In electrical terms, one watt-second is equivalent to one joule. A watt-second is a derived unit of energy that is equal to the power of one watt sustained for one second. A watt is a unit of power, or energy per unit time, and can be converted to energy units by multiplying by seconds. Thus, one watt-second is equal to one joule.
The relationship between the watt-second and the joule can be used to define the watt. For example, a 1-watt device consumes 1 joule of energy every second. To convert watts to joules, multiply the number of watts by the number of seconds the current runs. For instance, a 60-watt bulb uses 7200 joules in 120 seconds (60 watts x 120 seconds = 7200).
While the watt-second is equivalent to the joule in both units and meaning, there are some contexts in which the term "watt-second" is used instead of "joule". For example, in the rating of photographic electronic flash units.
RV Electrical Socket Replacement: A Step-by-Step Guide
You may want to see also
Explore related products
One joule is the energy needed to run a 1-watt device for one second
One joule is the unit of energy in the International System of Units (SI). In terms of SI base units, one joule corresponds to one kilogram-metre squared per second squared (1 J = 1 kg⋅m2⋅s−2). This is equivalent to the amount of work done when a force of one newton displaces a body through a distance of one metre in the direction of that force.
In electrical terms, one joule is the amount of energy needed to run a one-watt device for one second. This is also referred to as a watt-second (W⋅s), which is a derived unit of energy equivalent to the joule. A watt is a measure of power, or how fast energy is used, also known as energy over time.
A one-watt device consumes one joule of energy every second. For example, a 60-watt lightbulb uses 7200 joules of energy in two minutes. To calculate this, we multiply the number of watts by the number of seconds the current runs (in this case, 60 watts x 120 seconds).
One joule is also equivalent to the work required to move an electric charge of one coulomb through an electrical potential difference of one volt, or one coulomb-volt (C⋅V). This relationship can be used to define the volt.
London Flat Electricity: Getting Started
You may want to see also
Explore related products
One joule equals one newton metre
The joule (symbol J) is the SI unit of energy—a measure of the capacity to do work or generate heat. One joule equals the work done (or energy expended) by a force of one newton acting over a distance of one metre. One newton equals a force that produces an acceleration of one metre per second squared on a one-kilogram mass. Therefore, one joule equals one newton-metre.
The joule was named after James Prescott Joule (1818-1889), an English physicist and mathematician who helped develop the Kelvin scale. He also discovered the relationship between heat and mechanical work, leading to the law of conservation of energy, and subsequently, the first law of thermodynamics.
In 1935, the International Electrotechnical Commission (as the successor organisation of the International Electrical Congress) adopted the "Giorgi system", which redefined the joule. The Giorgi system was approved by the International Committee for Weights and Measures in 1946. The joule was now no longer defined based on electromagnetic units but instead as the unit of work performed by one unit of force (at the time not yet named newton) over the distance of one metre.
The joule is also defined as the energy dissipated as heat when a one-ampere electric current passes through a resistance of one ohm in one second. This is equivalent to the work required to move an electric charge of one coulomb through an electrical potential difference of one volt, or one coulomb-volt (C⋅V).
A watt-second (symbol W s or W⋅s) is a derived unit of energy equivalent to the joule. The watt-second is the energy equivalent to the power of one watt sustained for one second. While the watt-second is equivalent to the joule in both units and meaning, there are some contexts in which the term "watt-second" is used instead of "joule", such as in the rating of photographic electronic flash units.
Resetting Your GE Air Conditioner: A Step-by-Step Guide
You may want to see also
Explore related products
One joule is the energy dissipated by a current of one amp passing through a one-ohm resistance for one second
The joule is the unit of energy in the International System of Units (SI). One joule of energy is equal to the work done when a force of one newton moves an object through a distance of one metre in the direction of the force. It is also the equivalent of one watt-second, or one watt of power sustained for one second.
In electrical terms, one joule is equal to the energy dissipated by a current of one amp passing through a one-ohm resistance for one second. This relationship is the basis of Joule's Law, which states that when a one-ohm resistor carries a current of one ampere, it will dissipate one joule of energy in one second.
In a resistive circuit, electrical energy is converted to thermal energy, which is dissipated as heat. The more power transferred to the resistor, the hotter it gets. This is described by Ohm's Law, which states that one volt across a resistance of one ohm will cause a current of one amp to flow.
Therefore, one joule is equal to the energy dissipated by a current of one amp passing through a one-ohm resistance for one second. This is a fundamental relationship in electrical engineering and is used to calculate power in circuits.
Electric Force Invariance: Special Relativity's Impact
You may want to see also
Explore related products
One joule is equal to one coulomb-volt
In electrical terms, the joule is equal to one watt-second, which is the energy released in one second by a current of one ampere through a resistance of one ohm. A watt is a unit of power, which measures how fast energy is used, or energy over time. One watt-second is equal to one joule, and this relationship can be used to define the watt.
The joule is named after English physicist James Prescott Joule (1818-1889). The unit was adopted in 1935 by the International Electrotechnical Commission, which succeeded the International Electrical Congress. The Giorgi system, which redefined the joule, was approved by the International Committee for Weights and Measures in 1946 and ratified in 1948.
The joule is a fundamental unit of energy that is used to measure a variety of phenomena, including the energy required to lift a medium-sized tomato one metre, the heat required to raise the temperature of water from 0 degrees Celsius to one degree, and the energy released by an average person at rest every 1/60 of a second.
Stay Safe in Stormy Weather: Electric Jacket Guide
You may want to see also
Frequently asked questions
One joule is equal to the work done when a force of one newton moves a distance of one metre in the direction of the force. It is also equal to the amount of energy dissipated as heat when an electric current of one ampere passes through a resistance of one ohm for one second.
A watt-second is a derived unit of energy equivalent to one joule. It is the energy equivalent of one watt of power sustained for one second.
A watt is a unit of power, which is energy per unit time. Therefore, one watt is equal to a joule per second.
A volt is a unit of electrical potential difference. One joule is equal to the work required to move an electric charge of one coulomb through a potential difference of one volt.
A calorie is a unit of heat energy. One calorie is equal to approximately 4.184 joules, which is the amount of energy required to raise the temperature of one gram of water by one degree Celsius.
