Torque vs Horsepower: Meaning and Key Differences

Torque and horsepower are involved in measuring force. Torque means twisting or turning force, i.e., it indicates an engine's turning ability which makes a car accelerate. At the same time, horsepower refers to an engine's total power. In other words, torque enables the wheels to turn during acceleration. On the other hand, horsepower symbolises the speed you retain after acceleration.

This content covers everything about torque vs horsepower. To learn more, keep reading.

Torque refers to the moment of force. It measures the amount of force that can spin an object on an axis. In other words, force refers to the power that makes an object accelerate in linear kinematics. In a similar way, torque is responsible for causing an angular acceleration. This is why torque is also known as the rotational equivalent of linear force.

The straight line on which an object rotates is called the axis of rotation. From the physics perspective, torque refers to the tendency of a force to twist or turn. Various other terms describe torque, like moment or moment of force.

The torque magnitude is equal to the product of magnitude of force and the lever arm. The distance from the rotational axis up to the point where force is exerted is known as the lever arm. From the perspective of automobiles, the formula to calculate torque is given below:

Torque = Force x Distance

The SI system uses Nm or Newton-metre for determining the value of torque. The other units include kilogram-metre and feet-pound-force.

The term horsepower was coined by James Watt, the famous Scottish inventor. It is the figure used for measuring an engine’s power. It is often abbreviated as HP. In other words, it symbolises the capability of an engine.

In general, horsepower was formed on the basis of a horse lifting 33,000 pounds of water one foot in the air from the bottom of a 1,000-foot deep well.

However, when it comes to automobiles, horsepower refers to the full amount of power available in a vehicle. According to theory, horsepower directly relates to a car’s speed. This is because if the amount of horsepower is greater, the wheels will receive more power and run faster.

It is a unit of horsepower that compares a machine's power to a horse's muscle power. In the past, HP was applied for measuring a steam engine's power and potential with the power of horses. However, years later, application of this unit gradually started to flourish.

In this era, HP has a much broader application. It is applied to measure the power of turbines, electric motors, piston engines, as well as in automobiles.

1 Horsepower = 33,000 lb. ft. /min.

The formula of horsepower is:

HP = fd/t

Where, HP = Horsepower

d = distance (in feet)

f = force (in pounds)

t = time (in minutes)

Weight comprises the mass of entire body.

This formula is applicable for computing velocity of a vehicle immediately after the end of acceleration.