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Maximum Voltage Reading – ASE Practice Question (VIDEO)

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The Story of Dagmar Bumpers

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Should You Charge More When Dealing with Tire Sealant? (VIDEO)

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Testing Battery State of Charge – ASE Practice Question (VIDEO)

Description Technician A and Technician B are discussing battery testing. Technician A says that an open circuit voltage of less than 10.5 volts indicates a bad battery. Technician B says that a reading of 12.5 volts indicates an 80% state of charge. Who is correct?A)...

PSA: Be Safe With Carburetor Cleaner, Too

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The Real Meanings Behind OBD-II Diagnostic Trouble Codes (VIDEO)

Description When the check engine light (CEL) pops up and your OBD-II scan tool displays a code, that’s only the start of the diagnostic process. By breaking down the structures used to create DTCs, you can learn how to “decode” beyond the simple descriptions...

What’s Torque-to-Angle All About?

Torque-to-angle, also known as angle-torque or torque-plus-angle, is a fastening method that combines an initial torque application with a subsequent angular rotation to achieve precise bolt or fastener tension. This technique ensures consistent clamping force,...

What does horsepower really mean? (VIDEO)

by | Dec 17, 2024

Horsepower is a strange measurement, isn’t it? Think about it. When was the last time you used a horse for any kind of work or travel?

Like candlepower, the original horsepower attempted to express the output of a newer technology in comparison to its predecessor. Today, horsepower is one of the most common metrics we use to quantify vehicle performance, yet most of us in the auto repair industry have no experience with real horses at all. And even if we did, how would we meaningfully measure the work potential of a horse? How might that measurement of power translate to mechanical devices?

Thankfully, a clever guy named James Watt did the math for us over 240 years ago while developing steam engines that would kickstart the Industrial Revolution. This old Chevrolet video from 1937 does a fine job of explaining Watt’s journey to the earliest version of the horsepower measurement we know today. (The informational part of this video starts about two minutes in.)

Later advancements in power measurement made Watt’s horsepower obsolete with new variations like metric horsepower and imperial (mechanical) horsepower, but it is fitting that the International System of Units (SI) uses the watt as its standard for the same type of power measurement today.

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