How Fast Must You Drive to Experience a 210N Magnetic Force on Your Head?

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SUMMARY

The discussion centers on calculating the speed required to experience a magnetic force of 210 N on a charged object in Earth's magnetic field. Using the formula F = qvB, where F is the force, q is the charge (3e-9 C), and B is the magnetic field strength (5e-5 Tesla), the calculated velocity is 1.4e15 m/s. However, this result exceeds the speed of light (3e8 m/s), indicating that achieving such a force under these conditions is impossible. The conclusion emphasizes the limitations imposed by the laws of physics, particularly the speed of light as a fundamental barrier.

PREREQUISITES
  • Understanding of electromagnetic force equations, specifically F = qvB.
  • Knowledge of static electricity and charge, particularly the concept of charge in coulombs.
  • Familiarity with Earth's magnetic field strength, particularly at the equator.
  • Basic comprehension of the speed of light as a physical constant (3e8 m/s).
NEXT STEPS
  • Research the implications of the speed of light as a limit in physics.
  • Explore the concept of magnetic fields and their effects on charged particles.
  • Learn about static electricity and methods to measure charge.
  • Investigate real-world applications of electromagnetic forces in technology.
USEFUL FOR

Students studying physics, particularly those interested in electromagnetism, educators teaching related concepts, and anyone curious about the limits of physical laws in practical scenarios.

kiwikahuna
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Homework Statement


Oops, I forgot to add in the second part of the problem. Here's the original question plus the second part of the question.

The strength of Earth's magnetic field at the equator is approximately equal to 5e-5 Tesla. The force on a charge q moving in a direction perpendicular to a magnetic field is given by F = qvB, where v is the speed of the particle. The direction of the force is given by the right hand rule. Suppose you rub a balloon in your hair and your head acquires a static charge of 3 e-9 C. If you are driving east, how fast would you have to drive in order for the magnetic force on your head to equal 210 N (enough to knock you over)?




The Attempt at a Solution


Here's what I did but it seems too simple. Could anyone tell me if I'm actually doing this the right way or not? Thanks.
If force (F) = 210N
Then the formula for the velocity is
v = F / (Bq)
v = 210 N/ (5e-5 * 3e-9)
v = 1.4e15 m/s
 
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Assuming that the magnetic field is pointing straight up, your solution appears "correct" minus one little detail, that is, the speed of light is 3e8 m/s, and knowing that it is impossible to bypass this limit, the answer would be impossible.
 

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