What does torque measure

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Torque is present in everyday happenings, such as operating a doorknob, opening a soda bottle, using a wrench, or pedaling a bicycle. This applies torque, or a twisting force, to the bolt. While horsepower is simply measured in horsepower, torque is typically measured in pounds feet lb.

Applying one pound of force to the end of that one-foot long wrench exerts one lb. More torque can be applied by adding more weight, or, by using a longer wrench.

The lug nuts that attach the wheels to your car typically need to be tightened to about lb. All engines, whether gasoline or hybrid, generate a certain amount of both horsepower and torque. Eddy current dynamometers use a magnetic field to transfer torque from the spinning crankshaft to a lever arm bearing against a static force gauge known as a load cell spaced a precise distance from the center of the crank.

The perfect engine produces ample torque at low rpm and sustains that output to the redline. The amount of torque produced is directly proportional to the air flowing through the engine. Large engines pump more air and, therefore, produce more torque. Boosters—superchargers, turbochargers—deliver additional air to help small engines act large. Making up for the ease of injecting the right amount of fuel, engine designers face several difficult tasks.

Cooling and lubrication needs are roughly proportional to the power produced. And pumping air into, through, and out of any engine at ultra-high rpm is where engineering becomes an art form. But what about the greater moral issue confronting mankind in general and car enthusiasts in particular: Which is better? In a baseball game, if torque is analogous to the catcher, then horsepower is the pitcher.

New Cars. Buyer's Guide. In vehicles, the engines rotate around an axis, thus creating torque. It is the force that rockets a sports car from in seconds and pushes you back in the seat. It is also what powers big trucks hauling heavy loads into motion. These are the basics of horsepower and torque, but how are these concepts measured and how are they interrelated? Mathematically speaking, horsepower is the force needed to move pounds one foot in a second, or 33, pounds one foot in a minute.

Horsepower is found by measuring torque because torque is easier to calculate. Torque, as previously mentioned, is the expression of a twisting force and is measured in units of force times distance from the axis of rotation. So for instance, if you use a 1-foot-long wrench to exert a force of 10 pounds on the end of a bolt, then you are applying a torque of 10 pound-feet 10 lb-ft.

The units for torque are newton-meters Nm or pound-feet lb-ft. Newton or pound stands for the force that is acting, while meters or feet stand for the length of the lever arm.

Another name for torque that perhaps gives a clearer indication of its meaning is rotational force. As this name suggests, rotational force or torque ensures that an object rotates.

Force N , on the other hand, accelerates objects linearly. Engine power and torque are both indicators that depend on the engine speed. So, that was the theory — now for the practice. In combustion engine design, the aim is to provide the driver with high torque even at low engine rotation speeds. At the same time, the torque should be applied over the largest possible engine speed range.

In terms of driving experience, high torque means the shortest possible delay between the driver pressing the gas pedal and the engine responding. The driver perceives the high torque as great traction when setting off or overtaking. So, powerful torque applied early means a high degree of certainty when overtaking , great driving pleasure and efficient propulsion for the driver.

In short, high torque available early only offers advantages for drivers. Torque and its importance to drivers is best illustrated by its distinction from the term engine power or output. Put simply, it indicates the energy converted in a given period of time. It is quoted in kilowatts kW , formerly in horsepower hp. One watt W stands for one newton-meter per second, while 1 horsepower is the power required to lift 33, pounds exactly one foot in one minute.

An engine achieves high power either through high torque or high engine rotation speeds. The maximum engine power that the manufacturers advertise and that is also specified in the vehicle registration document is usually available at high engine speeds.