Can You Get More Than 11 Right on This Difficult Engine Quiz?


By: Zoe Samuel

6 Min Quiz

Image: Obradovic/E+/gettyimages

About This Quiz

There's a reason that the energy industry calls itself "the first five percent of the economy". Without them, there wouldn't be enough power for the rest of human existence to go on in the comfortable, post-industrial manner to which several billion of us have already become accustomed, and the remainder are starting to enjoy in increasingly large percentages. 

Still, all that power isn't much use if you don't have a mechanism by which to turn it into useful things. It'd be rather like having a very fast and impressive supercomputer that could code just about anything but had no input device such as a keyboard, or no screen. While a lot of the energy out there goes into electricity, a huge percentage also goes into engines. They're in cars, trains, airplanes, ships, pumps, factories and dozens of smaller gadgets that you could probably live without but really don't want to try. You use them every day whether you use transport or not, because they're essential to manufacturing and transporting the food you eat, the clothes you wear, the house you live in and just about everything else you touch.

However, just because we all depend on them doesn't mean we all know much about them. Even gearheads who can fix certain elements of their cars may struggle to know too much about how engines really work or what principles they depend upon. That's why this very difficult quiz will challenge even the biggest motorhead out there!

Where would you find a 3-phase traction motor?

The ACS-64 is a new locomotive that features these traction motors. Its name stands for Amtrak Cities Sprinter, and it helps bring the ageing Amtrak fleet up to date. These motors are particularly smart because they are electric, and also because they use regenerative power to save and re-use 15% of their energy, which increases efficiency.


"X has two openings for intake and exhaust, while Y only has an exhaust. They are otherwise the same." What type of engines are X and Y?

Rockets carry their fuel and oxygen with them, hence they only have an exhaust, instead of an intake. Other engines need air to make their fuel work, so they need an intake for air, as well as an exhaust.


What gets rammed in a ramjet?

A ramjet works by "ramming" air into the system to create a much higher-pressure combustion than would otherwise be possible, hence far more thrust. The idea came to French inventor Rene Lorin in 1908, though a ramjet was not built for some decades after.


What does a turbo engine add to the cylinder to increase the amount of thrust?

Regular internal combustion engines combust a mix of fuel and air. Turbo engines push a little extra air into the cyclinder to move pistons down with more force, which increases the oomph of the engine.


What is torque?

Torque is when you apply force in a straight line but it produces a rotational effect. For example, when you open a door, you apply force to the handle end of the door but you get rotation at the hinge side. Engines do the same thing to the crankshaft, thus driving the wheels to rotate.


What is special about a Wankel engine?

A Wankel engine has a rotary instead of a piston motion. This is much more efficient but presents lots of issues in actually making it work. Wankel engines were invented in the 1950s but generally didn't find a lot of commercial uses until the last 20 years.


What did Hero (or Heron) of Alexandria build in 50 B.C.?

Heron's model was just a toy where you heated up water which drove a sphere to spin and thus cause a little pair of fins to twiddle. However, it used all the principles of the Industrial Revolution. It's likely a copy of the plans burned in the Great Library of Alexandria.


Which of these is the best definition of an engine?

Engines are machines that convert energy into motion. For example, a steam engine burns a fuel source like coal to generate heat, which turns water into steam, which drives pistons. These are connected to a pump or axles, where the energy becomes motion.


Who invented the crankshaft?

Ismail al-Jazari invented the crankshaft in 1206. As we see with Heron of Alexandria, there were a lot of opportunities back in older times for the Industrial Revolution to start earlier, but unfortunately society wasn't connected or rich enough to make it happen. That means even brilliant minds like al-Jazari didn't get to flourish as much as they should have.


Who built the first "atmospheric engine" in 1673?

Huygens built this engine in the 1600s but could only get it to move one stroke at a time. An engine only provides value if it goes up and down continuously, which other thinkers were able to crack using Huygens' work - meaning he was yet another brilliant mind trapped before his time.


Which of these is true?

Motors and engines both use power to supply movement. Motors specifically have to supply movement to a machine, so not all engines are motors, but some are. Motors run on electricity or combustion, while engines only run on combustion, so not all motors are engines, but not all. Thus electric cars arguably have a motor but no engine.


What fuel was used in The Rocket, George Stephenson's famous early locomotive?

Coke is what happens when you heat coal without any air. This removes impurities and provides a nice energy-dense fuel that has all the upsides of coal but few of the downsides.


What is the "gas" in early "gas-powered" engines?

Natural gas is mostly methane, which contains a lot of energy and is a fine source of power (carbon emissions that endanger the planet notwithstanding!). It's the "gas" that is in early gas engines, instead of gasoline or petroleum.


Which of the below is the best definition of "combustion"?

Combustion is like burning except that the latter produces flames - that is, heat and light. Combustion likewise creates energy and is a kind of burning, but a more specific kind involving oxidation - and hopefully, motion instead of flames.


Which of these key engine components was invented by Edward Butler?

Butler's work was key to the production of early cars, which had more components in them than you'd think. Foremost among the users of his ideas was a certain Gottlieb Daimler, who you may have heard of!


How did the patent for the first car describe it?

It had a gas engine, and so that's how it was described. Of course, it was in German, but the translation above is pretty solid. Patents are an essential part of the invention process as they enable monetization of ideas, which means investment and research.


When it comes to converting energy into motion, what alternative to the piston was known to be possible in the 1800s, but didn't put out net power until 1903?

Turbines were the dream goal of a lot of inventors in the 1800s, but they always used more energy than they put out. Norwegian Ægidius Elling build the first turbine that put out a net plus, and now of course, that principle is key to wind technology, which is due to overtake natural gas as the second-cheapest form of energy (solar is cheapest). Technology really does change quickly when the investment is there!


What was the maximum weight the Wright Brothers settled on for the engine in their first successful flight?

The Wright Brothers didn't build all their own stuff, though they did build a lot of it. They were a rare combination of mechanical genius and daredevil insanity.


What does a vehicle powered by a ramjet need to do before it uses its ramjet?

Ramjets only work when the outside air is going very fast. That means vehicles that use a ramjet need a conventional jet engine to get up to speed before turning on the ramjet.


When did the first electric car drive up a hill?

You couldn't buy a Prius until the 1990s, but the electric car is actually older than cars that drive on liquid fuel! It was invented by Robert Anderson, an oddball who put a little electric motor and a battery on a carriage and drove it up a hill. Electric cars were king until lack of electrical infrastructure, Henry Ford and rising mass production made the fuel-powered cars cheaper.


What does the "scram" in scramjet stand for?

If you fly a ramjet-powered plane really fast, it gets more and more efficient until Mach 5, when it starts to get less efficient due to having to slow down the air that it takes in before combusting it. Enter scramjet, which doesn't have to do this, and can thus go super-duper fast. Scramjet can fly about 7,000 mph!


What does OPOC stand for?

OPOC is a modern engine based on an old idea. As the electric car supplants the internal combustion engine, other new layouts and ideas are springing up, and OPOC is one of them.


Where might you find a rotary engine in something you use every day?

Since you're a forward-looking person who hates paying for fuel and maintenance, you've probably got an electric car already. OK, maybe not, but you're probably going to have one soon, because internal combustion engines are being banned in a lot of countries and EVs are already cheaper. One of the fun elements in your EV might be the rotary engine in the range extender.


For what primary purpose were the first commercial-scale engines used?

The Industrial Revolution started with coal as much as anything, and if you want to have a safe(ish) mine to work in, pumping out the water is a must. The ability to partially automate this by using an engine instead of hand or animal power was a huge factor in the coal-fueled revolution taking off.


What kind of engine did NASA put in the probe Dawn, which visited the dwarf planet Ceres?

An ion thruster sounds like something out of Star Trek, but it's real! NASA has one in development that could get humanity to Mars in under two months.


What did Taqi al-Din create in 1577, that inspired many later thinkers and helped undergird the Industrial Revolution?

Taqi al-Din is one of the giants of the Islamic Golden Age whose name ought to be as familiar as James Watt. He was a Newtonian figure who kept inventing things that nobody else in his time could comprehend. He became rich and famous as a result, but alas, not outside his own time.


Which of these is not a real unit involved in engines?

A wisp is not a unit of energy. Watts, volts and ohms respectively measure power, speed of current and resistance of a wire. Thus you need to be able to calculate all of them to make your engine go. They're all named for pioneers of relevant technology.


When you fractionally distill crude oil to make fuel for engines, which fraction is distilled first, out of the below?

There's a handy mnemonic to remember the order of distillation in crude oil: grand-parents never knock down friendly little boys. That is, gasoline, petroleum, naphtha, kerosene, diesel, fuel oil, lubricant oil, and bitumen!


What's the key difference between steam and internal combustion engines?

The difference is that steam engines need a continuous source of heat but combustion engines don't. That's why steam takes a while to get going by building a "head of steam" while the other just needs ignition.


What is one horsepower, in watts?

For some reason, James Watt decided to make horsepower a super annoying amount of energy for people who'd prefer to calculate with round numbers. He was brilliant, sure, but he didn't care how much misery he inflicted on generations of school students.


What does the V in V8 stand for?

The cylinders in a V8 or V6 etc are lined up in two sets of three or four. These are typically set at an angle from one another, which means they create a V shape. So the V is just describing what's right there!


Which of the below was NOT involved with the invention of the motorcycle?

Daimler and Maybach both worked for Otto, who sued them for stealing his work, even though he later got in trouble for stealing patents himself. Benz was a contemporary and competitor of the other three.


In what plane would you find the Rolls-Royce/Snecma Olympus 593 engine?

Concorde was a supersonic passenger jet that sadly doesn't fly anymore, as the economics of it were too challenging. However, it was a technological marvel and the ideas used to produce it are currently being used to generate a new generation of lighter, more affordable supersonic commercial airliners that you should expect soon, coming to a sky near you!


How many moving parts are in a Tesla motor?

There are two moving parts in the Tesla motor. Both are involved in making the drive train go. This is one reason that electric vehicles are so quiet and also practically maintenance-free; they have about 1% (that's just one, not a typo!) of the total moving parts of a traditional car.


How does an engine muffler work?

If you bounce soundwaves into each other so the peaks and troughs line up just so, they cancel out. It's a matter of designing your muffler so the angles are just right.


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