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

AI Thread Summary
To experience a magnetic force of 210N on the head while driving, the calculation involves using the formula F = qvB, where the Earth's magnetic field at the equator is approximately 5e-5 Tesla and the static charge acquired is 3e-9 C. The calculated velocity required to achieve this force is 1.4e15 m/s, which exceeds the speed of light at 3e8 m/s, indicating that such a scenario is physically impossible. This highlights the limitations of classical physics in extreme conditions. The discussion emphasizes the importance of recognizing the constraints imposed by fundamental physical laws. Ultimately, the conclusion is that the scenario described cannot occur in reality.
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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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