Power refers to the rate at which work is done or the rate at which energy is transferred. Power is measured in units of horsepower (hp) or kilowatts (kW). Torque refers to the twisting force that an engine can generate. Torque is measured in units of pound-feet (lb-ft) or newton meters (Nm).
- Power is the rate at which work is done, or energy is transferred, while torque is a rotational force that causes an object to rotate around an axis.
- Power depends on torque and engine speed, with higher torque and speed resulting in greater power output.
- Torque is more critical for acceleration and towing capacity, while power is important for top speed and maintaining high speeds.
What is Power?
Power refers to the ability or speed at which a machine can do its required work. Power can also be alternatively called as horsepower. A vehicle’s power is directly proportionate to its speed and acceleration.
In other words, when a vehicle is said to have high power, it also means that it will have top-notch speed and acceleration. One power or horsepower (hp) measures approximately 0.746 kilograms. Horsepower, or power, however, can be of two types:
- Mechanical horsepower
- Metric horsepower
The term Horsepower or Power was first used during the 18th century to draft a comparison between steam engines and draft horses. The term was curated by a Scottish engineer whose name was James Watt. Most countries now around the world use watts as a measure to define power.
In modern days, power when opting to buy a car is so important because it will define how one’s car performs on the road. A car with fewer horsepower will have lesser speed and acceleration than one with more. Thus, if one travel a lot by land then having a car with good horsepower is important to cover long distances.
What is Torque?
Torque can be defined as the force that is made by a car’s engine. It is the pulling force of the engine or a machine. The heavier the machine or vehicle is the greater is the need of torque in their engines. Torques helps with the spinning of initial inertia for acceleration. High torque energy is needed when a machine is performing with heavy work loads or a car is working towards high inclined areas. Higher Torque helps heavy vehicles or machines to get its job done at ease.
The term torque is derived from the Latin dictionary which means ‘to twist’. Thus signifying its job done at initial acceleration. The word torque is said to have been first used in 1884 by the brother of lord Kelvin, James Thomson.
Torque is a rotating force of an object about its axis or at a fixed point. The unit of torque at which it is measured is Newton-meter also can be used as nm.
There are two types of torque. They are:
- Static Torque
- Dynamic Torque
Any kind of torque that does not provide bifurcated acceleration is static torque. While torque that provide angular acceleration is dynamic torque.
Difference Between Power and Torque
- Power is defined as the ability or speed at which a machine can do its required work, while torque is defined as the rotating force of an object about its axis or at a fixed point.
- The International System of Units for power is the watt, while the International System of Units for torque is the newton-meter.
- The symbol that represents power is the exponent symbol (^), while the symbol that represents torque is the Greek letter tau (τ).
- Power is a greater concept as it defines the whole process of ability or speed of a machine, while torque is a narrower concept as it defines a fixed point at an axis during initial acceleration.
- The mathematical formula for power is work divided by elapsed time, while the mathematical formula for torque is radius multiplied by force multiplied by sin theta. (Sin θ).
Comparison Between Power and Torque
|Parameter of Comparison||Power||Torque|
|Definition||Power is the ability or speed at which a machine can do its required work.||Torque is defined as the rotating force of an object about its axis or at a fixed point.|
|Symbol||The symbol of power is ^.||The symbol of torque is τ.|
|SI unit||The SI unit of power is Watt.||The SI unit of torque is Newton-meter.|
|Concept||Power is a wider concept as it covers a machine’s whole ability or speed.||Torque is a narrower concept as it only focuses on a fixed point during initial acceleration.|
|Formula||The formula of power is P = E/t Where, P= Power E= Energy t= time in seconds.||The formula of torque is Γ=r×FxSinθ.|
|First used||The term power was first used by James Watt, a Scottish engineer.||The term torque was first used by James Thomson, brother of lord Kelvin.|
|Discovered||The term power was first discovered in the 18th century.||The term torque was first discovered in 1884.|
Want to save this article for later? Click the heart in the bottom right corner to save to your own articles box!
I’ve put so much effort writing this blog post to provide value to you. It’ll be very helpful for me, if you consider sharing it on social media or with your friends/family. SHARING IS ♥️
Piyush Yadav has spent the past 25 years working as a physicist in the local community. He is a physicist passionate about making science more accessible to our readers. He holds a BSc in Natural Sciences and Post Graduate Diploma in Environmental Science. You can read more about him on his bio page.