Induced EMF and long steel beam

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SUMMARY

The discussion focuses on calculating the induced electromotive force (emf) in a 5.97 m long steel beam dropped from a height of 6.82 m, with a horizontal magnetic field of 12.2 µT. The acceleration due to gravity is 9.8 m/s². The user correctly applies the equation for motion to determine the time of fall as 0.834 seconds. The concept of "motional emf" is introduced, emphasizing the need to calculate the speed of the beam just before impact to find the induced emf accurately.

PREREQUISITES
  • Understanding of electromagnetism principles, specifically induced emf.
  • Familiarity with kinematic equations of motion.
  • Knowledge of magnetic fields and their interaction with conductive materials.
  • Basic calculus for understanding change in flux over time.
NEXT STEPS
  • Study the concept of "motional emf" in detail.
  • Learn how to apply Faraday's Law of electromagnetic induction.
  • Research the effects of magnetic fields on moving conductors.
  • Explore practical applications of induced emf in engineering contexts.
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Physics students, electrical engineers, and professionals involved in construction and safety assessments related to electromagnetic fields and induced currents.

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A 5.97 m long steel beam is accidentally dropped by a construction crane from a height of 6.82 m. The horizontal component of the Earth's magnetic field over the region is 12.2 [tex]\mu T[/tex]. The acceleration of gravity is 9.8 m/s^2. What is the induced emf in the beam just before impact with the Earth, assuming its long dimension remains in a horizontal plane, oriented perpendicularly to the horizontal component of the Earth's magnetic field? Answer in units of mV.

I know that E= change in flux/change in time
To get the change in time I used the equation
x(t)= x_o +v_o*t +.5 gt^2
where x_o=v_o=0
and x(t)= 6.82 m.
solving for t gave me .834 s.
Then for the flux I think it's just B*L= 72.8... but I don't think that's right...
Can someone please help me?
 
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review something called "motional emf." THere is a variation of the emf formula for a straight conductor moving through a magnetic field in terms of its speed. Then, all you need to do is find the speed of the bar as it reaches the ground.
 
I got it... Thanks!
 

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