Spider-Man's Greatest Strength Are His Webs

 BREAKING: Spider-Man’s Greatest Power is His Webs 

So there I am, sitting in my bed rewatching Spider-Man: No Way Home for like, the millionth time. But this time it’s different, because I’m currently enrolled in a physics class, so I’m starting to see the world in terms of physics problems (much to my own chagrin). As I’m watching the movie, I watch in newfound physics-based astonishment as Spider-Man catches a mid-size car with his webs as it falls off of an overpass. It was a fundamental physics professor’s dream: the tip of the car just touches the ground before Spider-Man’s webs bring the car back up. Naturally, I had one question: how strong are those webs?!

I started by drawing a diagram of the situation. As shown in the scene, Spider-Man’s webs attach to the car while it’s still on the overpass, so I am assuming that they extended about 10 feet (3.048m). I then searched for the average height of an overpass and the average mass of a mid-size car. I found that the average height of an overpass is somewhere between 14-16 ft1, but the camera made it look even taller, so I called it 20 ft. The average mass of a midsize car is 1500 kg2. The average height of a car is 5 ft3,, but that doesn’t actually make a difference. 

Figure 1. The parameters.

I defined the “strength” of the webs as their spring constant (we do not yet know how to calculate the tensile strength, but that would have been interesting). In order to find the spring constant (k) of the webs, I first needed to determine the velocity at which the car would have been traveling while freefalling 10 ft while the webs were not stretched: 

Figure 2. Initial velocity calculations

Using this velocity as the initial velocity of the car right before the webs started to stretch, then used the conservation of energy equation to calculate the total work done by the webs (I called it Wspring for the sake of clarity). Once I had the (very large in magnitude) work of the webs, I was able to calculate the force of the webs and the spring constant: 

The webs exerted 27812.69 N of force onto the car and they have a spring constant of 9124.9 N/m. Sure, whatever that means. My next question was: well, how strong is that? I decided to compare it to stainless steel springs. The maximum spring constant of any thin, stainless steel spring I could find was 0.053 N/mm, or 53 N/m (source 4). Spider-Man’s webs are 172 times stronger than a steel spring. That’s pretty strong to me. 

Sources: 

1. https://www.google.com/search?q=average+height+of+an+overpass&rlz=1C5CHFA_enUS901US901&oq=average+heigh&aqs=chrome.2.69i57j69i59l2j0i433i512j0i512l6.3940j0j9&sourceid=chrome&ie=UTF-8

2. https://www.google.com/search?q=average+mass+of+a+car&rlz=1C5CHFA_enUS901US901&oq=average+mass+of+a+car&aqs=chrome..69i57j0i512j0i15i22i30l3j0i22i30l5.5000j1j9&sourceid=chrome&ie=UTF-8

3. https://www.google.com/search?q=average+height+of+a+car&rlz=1C5CHFA_enUS901US901&oq=average+height+of+a+car&aqs=chrome.0.69i59j0i512l6j0i22i30l3.4389j1j9&sourceid=chrome&ie=UTF-8

4. https://www.acxesspring.com/espanol/spring-constant-calculator.html