Veritasium - The Google Interview Question Everyone Gets Wrong
The discussion begins with the famous Google interview question about being shrunk to the size of a nickel and placed in a blender. Various humorous and creative solutions are proposed, but the video delves into the physics and biology to find a feasible answer. The concept of jumping out of the blender is explored, supported by the idea that smaller creatures have higher strength-to-weight ratios, allowing them to jump higher relative to their size. This is demonstrated through simulations and comparisons with animals like squirrels and ants. However, the video also highlights the biological challenges of being shrunk, such as the inability of a human heart and lungs to function at such a small scale. The video concludes by discussing the purpose of such brainteasers in interviews, emphasizing that they are more about assessing problem-solving skills and creativity rather than finding the correct answer. Despite their impracticality in hiring, these questions encourage innovative thinking and have historical significance in scientific discoveries.
Key Points:
- Smaller creatures have higher strength-to-weight ratios, allowing them to jump higher relative to their size.
- Biological challenges exist when humans are shrunk, such as heart and lung functionality issues.
- Google's brainteaser questions were more about assessing problem-solving and creativity than finding correct answers.
- The video uses simulations to demonstrate the feasibility of jumping out of a blender when shrunk.
- Brainteasers, while impractical for hiring, encourage innovative thinking and have contributed to scientific discoveries.
Details:
1. 🌀 Famous Google Interview Question
- Google received about 3 million applications each year but hired only 7000 people, resulting in a 0.2% acceptance rate.
- Brainteasers like the blender question were used to screen applicants, as interviewers made these questions up for fun.
- The blender question involves imagining being shrunk to the size of a nickel inside a blender with blades starting in 60 seconds.
- Responses to the blender question included attempts to break the blender, use clothes as a rope, or hide under the blades.
- The question has been widely debated in forums like Reddit, with no universally accepted answer.
- The purpose of such questions was to assess creative problem-solving abilities under pressure.
- Other examples of Google interview questions include estimating the number of piano tuners in a city, which tests logical thinking and estimation skills.
2. 🦎 Van der Waals Forces and Climbing
- Geckos utilize Van der Waals forces for climbing, leveraging millions of tiny branches in their feet to maximize surface area and mold to surfaces.
- Van der Waals forces, though weak, are effectively used by geckos due to their specialized foot structure, similar to forces holding graphite layers in pencils.
- Ants and cockroaches employ different mechanisms like tarsal claws for frictional attachment, even on smooth surfaces, exploiting surface imperfections.
- Human anatomy lacks gecko-like branches or insect claws, making climbing using Van der Waals forces impractical.
- Effective human climbing would require slow and precise limb placement, impractical for quick ascents.
3. 🏃♂️ Jumping Out of the Blender
- The discussion uses a metaphor of being inside a blender to explore problem-solving strategies, highlighting the need to escape a complex situation.
- Participants express feelings of embarrassment and a lack of knowledge despite nearing their degree completion, illustrating a common struggle of applying academic concepts practically.
- Entropy is mentioned as a scientific principle, suggesting that increasing chaos and system disruption could lead to a solution, though the transition from the metaphor to this concept could be clearer.
- A suggestion is made to avoid overthinking and consider the simplest solution: 'just jump' out of the blender, emphasizing the importance of straightforward thinking in complex problems.
- Quantum Tunneling is humorously considered as a complex scientific solution which seems impractical, indicating the limitations of applying high-level physics to everyday challenges.
- The notion of jumping out initially seems irrational, but it provokes curiosity about understanding and simplifying complex issues.
4. 🐿️ Size and Jumping Ability in Animals
- Smaller and lighter animals can jump significantly farther relative to their body size compared to larger animals, a concept first observed by Alfonso Borrelli in the 17th century.
- Despite a 1500-fold difference in weight, horses and squirrels can jump to roughly the same height due to similar muscle-to-weight ratios, illustrating how muscle efficiency impacts jumping ability across different sizes.
- In species where survival depends on jumping, such as squirrels, their jumping ability is optimized, unlike species such as turtles and elephants where this trait is not essential.
- Strength in animals is determined by the muscle cross-sectional area, which scales with the square of their height, explaining why smaller animals like ants exhibit remarkable strength relative to their size.
- This understanding of size and jumping ability provides insights into animal behavior and adaptation strategies, where jumping is a critical survival mechanism for some species.
5. 💪 Strength-to-Weight Ratios
- Smaller animals have higher strength-to-weight ratios because as they scale down, their weight decreases faster than their strength.
- Humans, if scaled down, could potentially lift their own weight multiple times, similar to how smaller animals can.
- In hypothetical scenarios like being shrunk, humans could exhibit extraordinary capabilities such as jumping out of a blender due to increased strength relative to their weight.
- Inaccuracies in media portrayals, such as movies where shrunken people struggle with lifting objects, ignore the scientific reality of increased strength-to-weight ratios.
6. 🤔 The Complexity of Jumping
- Jumping is a complex biomechanical action that requires not only strength relative to weight but also precise timing and kinetics, such as maximizing ground contact time to apply force effectively.
- Skepticism exists around the notion that reducing a person's size drastically enhances their jumping ability due to the non-linear nature of scaling physical capabilities.
- Accurate modeling using physics equations is vital to understanding the limitations and potential of jumping when scaling down human size.
- An example illustrates that a person weighing 84kg and jumping 27cm high, when scaled down to 1% of their original size, would only achieve a jump height of 42cm, demonstrating that size reduction does not lead to a hundredfold increase in jump height.
7. 💨 Air Resistance and Jumping Simulation
- Air resistance has a significant impact on jumping, particularly when the cross-sectional area increases relative to weight, such as by 100 times when considering a nickel-sized area.
- Without air resistance, the initial jump height is 42 cm, but with air resistance, it decreases to 39 cm, demonstrating a 3 cm reduction due to drag.
- If the jumper flips onto their side, exposing ten times the surface area, the jump height further decreases to 22 cm, illustrating the drastic impact of increased drag.
- Acrobatic maneuvers like a backflip can significantly increase air resistance, reducing the likelihood of a successful jump due to the increased surface area exposed to drag.
8. 🧠 Biological Feasibility and Intuition
- The proposed jumping mechanism requires applying a force in 1/1000 of a second and undergoing 278 G's, which is biologically infeasible for survival.
- Simulations show a model can jump 40cm, but practical intuition suggests such feats are not possible for living creatures.
- The discussion highlights the importance of intuition in assessing biological capabilities, suggesting over-reliance on simulations can be misleading.
9. 🎯 Google's Perspective on Brainteasers
- Google has moved away from using brainteasers in interviews, finding them ineffective for evaluating candidates.
- Biological experts argue that reducing human size is impractical due to the inability to sustain life functions like breathing and blood circulation.
- The complexity of the human brain, with 86 billion neurons, cannot be maintained in a smaller volume, making such scenarios unrealistic.
- Cellular structures cannot be reduced without losing functionality, challenging the feasibility of hypothetical size reduction.
- Physicists are divided on whether reducing size would lead to superhuman abilities or loss of strength, highlighting the speculative nature of such questions.
10. 🧪 The Value of Thought Experiments
- Google interviewers prioritize assessing attributes like addressing ambiguity, problem breakdown, creativity, intelligence, and communication over finding the correct answer.
- Google's VP of People Operations, Laszlo Bock, stated that brain teasers in interviews do not effectively predict candidate success and primarily serve to make the interviewer feel smart.
- While brain teasers are ineffective for job interviews, they inspire creativity and new perspectives, similar to historical scientific discoveries.
- Examples of thought experiments that led to major scientific advancements include Einstein's theory of relativity, Euler's graph theory, and Schrödinger's illustration of quantum mechanics.
- Embracing seemingly ridiculous or silly questions can lead to profound insights and help in learning new concepts.