Feeling rusty with Engineering Fundamentals?
Or worried about passing the FE or PE exam?


LEARNerds gets you back up to speed, by making Engineering Practice
a fun, motivating, ridiculously-simple part of your daily routine.

Every morning at 7AM (EST) we jumpstart your day with a daily Engineering Question,
similar to concepts found on the Fundamentals of Engineering Exam (FE) & Professional Engineering Exam (PE).

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Walk the Plank

You’re back at the playground, one engineering degree later. Now you’re a playground engineer! (We swear that’s a position)

Your current task is to build a pirate ship themed playground. You’re designing a “walk the plank” section, but then realize some dumb adult could break it. The plank is 6 feet and fastened to the edge of the ship. Let’s say that the average adult male weighs 180 lbs, but when he jumps, it doubles to about 360 lbs.

What amount of torque should the joint be expected to support from the childlike adult?


      1080 lbft
      2160 lbft
      3600 lbft
      4800 lbft

Part of the puzzle (of life) is uncovering implicit clues, while deciding what assumptions to make. So comment on any ambiguities you see so others can learn to spot them too!

Merry Go Round - Lesson in Torque

They just installed a new merry-go-round in the park, and it makes you realize the old one isn't quite as good. For one, the old one always took more work to spin and it never stayed spinning very long, no matter how much they oiled it. And the old one would speed up and slow down on its own. Probably because the center pole was crooked to the ground. Your grandfather says, "The old one has less torque". What does he mean by torque?

Hint: there may be more than one right answer...

Part of the puzzle (of life) is uncovering implicit clues, while deciding what assumptions to make. So comment on any ambiguities you see so others can learn to spot them too!

Bullet Ballistics - Calculating Minimum Muzzle Velocity

To our mail subscribers - sorry for the strange email earlier! Our mail delivery system went temporarily rogue. Here's today's actual question!


You're one crime scene away from the weekend.

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In this scenario, you find a 8.2 gram lead bullet that was stopped in a doorframe. It's melted completely on impact. Assuming the bullet was shot at room temperature (20° C), what do you calculate as the minimum speed the bullet leaves the gun (aka its minimum muzzle velocity)?

Note: Let's say lead melts at 327°C, and its specific latent heat of fusion (melting) is 2.5 * 10^{4} J/kg.

(Stuck? Check the hint)


      223 m/s
      283 m/s
      360 m/s

Part of the puzzle (of life) is uncovering implicit clues, while deciding what assumptions to make. So comment on any ambiguities you see so others can learn to spot them too!

Bridge Collapse - Count the Bananas

Everyday Harry and his crew work tirelessly to pick bananas and deliver them across this rickety bridge. However today, Harry's crossing with a slightly larger load. He gets about 1/3 the way into the bridge, then notices a sudden SNAPPING sound. Alarmed, he unfastens himself from his mule and scurries back up the bridge... Instantly the rope bridge snaps, sending bananas flying everywhere! Thankfully, Harry survives. But his mule & bananas... not so much. 

Distraught as he is, Harry still needs to recover the loss of his bananas. And he needs YOU to help figure out exactly how much he lost. He brings you a sample of the bridge rope. You test the rope to find its max tension at 14,630N. Later, you learn the bridge was 300m long and covered a 225m gap. Measurements from the ground also reveal that the banana load landed 50m from the cliff wall. And the mule + cart together weighed about 400kg. How much was Harry's banana load?

Note: The tension in a standard bridge is distributed among 2 ropes.


      1000kg
      2000kg
      3000kg
      4000kg
      NOT THE MULE!!!

    Part of the puzzle (of life) is uncovering implicit clues, while deciding what assumptions to make. So comment on any ambiguities you see so others can learn to spot them too!

    Recreating the Car Collision - Guilty of Speeding?

    Another day, another collision to investigate...

    You arrive at the scene of a car accident (a street intersection), and are asked to determine if any of the cars involved were speeding.

    You immediately begin gathering information, and note the following:

    • A sunny day, which means the accident occurred on dry concrete. Both cars have standard rubber tires. A quick glance at a reference table tells you the coefficient of kinetic friction is 0.68.
    • Car #1 approached from the North. The model has a mass of 2675 kg.
    • Car #2 approached from the West. The model has a mass of 1640 kg.
    • The accident occurred in a 30 MPH zone.
    • Witnesses say the two cars stuck together upon impact until coming to a complete stop.
    • You measure a 13.9m long skid mark 66° South of East (a.k.a 294°).

    So...anybody guilty of speeding here?

    Part of the puzzle (of life) is uncovering implicit clues, while deciding what assumptions to make. So comment on any ambiguities you see so others can learn to spot them too!