G-Force and (possibly) Centrifugal force applied to the rotation of a car

In summary, the scene from "The Iron Giant" where the Giant rotates his torso with Hogarth inside is an example of misapplied physics. The filmmakers failed to accurately portray the effect of centripetal forces on Hogarth, and the calculated G-force should be much higher than what was shown in the movie.
  • #1
SignSeeker7
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1. I'm in my first year of physics, and the end-of-year project is a bit of a doozy: find two examples of misapplied physics in movies and explain how it's wrong. For my first example, I chose a scene from the movie "The Iron Giant," in which the Giant picks up a car with Hogarth, our child protagonist, inside, and then rotates his torso incredibly fast, like a merry-go-round. I noticed that despite the incredible speed, no "centrifugal" force was being applied; Hogarth was sitting in the driver's seat, but not moving towards the outside of the car.
I'm having trouble with the centrifugal force, which I believe is an equal-but-opposite reaction to centripetal force (though I'm not quite sure), and calculating the G-force, which I'm not sure how to do.

radius- assuming Hogarth's claim that the Giant is 100 ft. tall, and that the Giant is similarly proportional to a human, the radius - the length of his arm- would be approximately 50 feet, or 15.24 meters.
Speed- about 5 revolutions in 2 seconds- 150 revolutions in 1 minute, or 1 revolution in 0.4 seconds.
Velocity- 239.39 meters/second.
Mass- assuming the mass of the car is about 5000 lbs. and Hogarth is about 80 lbs., then their combined total is about 2304.25 kg.
Centripetal acceleration- 3,755.94 meters per second squared
Centripetal force- 8,654,630 N

2. Ac = V squared / r
V = (2∏r)/T
Fc = (m[V squared]) / r
3. I've found a bunch of factors, but I'm not sure how they relate to each other and how they show that Hogarth should be suffering from more G-force and moving outwards.
And I'm not sure I'm even applying the correct equations or principles, or if what I'm trying to find is what I actually need to find.
 
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For the scene in question, you need to calculate the G-force that Hogarth would be experiencing as the Iron Giant rotates his torso. This can be done by calculating the centripetal acceleration and then multiplying it by the mass of the car and Hogarth, which can be found from the radius, speed, and mass. Centripetal acceleration is given by the equation: Ac = V^2/r, where V is the velocity and r is the radius. To find the velocity, use the equation: V = (2*π*r)/T, where T is the time it takes for one revolution. Once you have the centripetal acceleration, you can find the centripetal force by multiplying it by the mass of the car and Hogarth. Finally, you can calculate the G-force by dividing the centripetal force by the mass. Therefore, the G-force that Hogarth should be experiencing is much higher than what was depicted in the movie. This is an example of misapplied physics, as the filmmakers failed to take into account the effect of centripetal forces on Hogarth as the Iron Giant rotates.
 

1. What is G-force and how does it affect a car's rotation?

G-force, or gravitational force, is the force exerted on objects due to the Earth's gravity. In the context of a car's rotation, G-force is the force that acts on the car and its occupants as the car changes direction or speed. This force can cause a feeling of weightlessness or heaviness, depending on the direction of the rotation.

2. How is G-force measured in a car?

G-force is measured in units of acceleration, typically in g-forces. One g-force is equal to the force of gravity on an object at rest on Earth's surface. In a car, G-force can be measured using an accelerometer, which is a device that measures changes in speed and direction of an object.

3. What is centrifugal force and how does it relate to a car's rotation?

Centrifugal force is the apparent outward force that acts on an object as it rotates around a central point. In the context of a car's rotation, centrifugal force is the force that pulls the car and its occupants away from the center of the rotation. This force is caused by the car's inertia and the curvature of the path it is traveling on.

4. How is centrifugal force affected by a car's speed?

The greater the speed of a car, the greater the centrifugal force acting on it. This is because as the car moves faster, it experiences a greater outward force due to its inertia and the curvature of its path. This is why cars can handle tight turns at lower speeds, but may lose control at higher speeds.

5. How can G-force and centrifugal force be managed in a car's design?

Car designers use various techniques to manage G-force and centrifugal force in a car's design. This can include designing the car's suspension and tires to provide better grip on the road, as well as incorporating features like anti-lock braking systems and stability control to help the car maintain control during high-speed turns. Additionally, race car drivers use their body positioning and techniques such as "trail braking" to manage G-force and maximize the car's performance.

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