Department of Energy Argonne National Laboratory Office of Science NEWTON's Homepage NEWTON's Homepage
NEWTON, Ask A Scientist!
NEWTON Home Page NEWTON Teachers Visit Our Archives Ask A Question How To Ask A Question Question of the Week Our Expert Scientists Volunteer at NEWTON! Frequently Asked Questions Referencing NEWTON About NEWTON About Ask A Scientist Education At Argonne Electromagnetic Pulses
Name: N/A
Status: N/A
Age: N/A
Location: N/A
Country: N/A
Date: N/A


Question:
When's there's a nuclear blast, how does it create the EMP?



Replies:
When a nuclear blast occurs, a number of things happen at once. Many high-energy photons (x-rays and gamma rays) are produced. These photons collide with electrons in the bomb debris or the surrounding air and strip them from their nuclei. This causes a movement of the electrons away from the atomic nuclei. This separation of charges generates an electric field, and the motion of the charged particles (electrons) also induces a magnetic field. Magnetic and electric fields that change with time are all you need to generate electromagnetic radiation.

Because of the high energy of a nuclear explosion and the high temperature of the fireball, these electromagnetic pulses pack quite a whallop. The frequency of the radiation in an EMP is fairly low, just in the range that electronic devices are sensitive to. Susceptible electronic circuits act as receivers, and pick up damaging voltage and current surges. The electronic components overheat, and that's the end of the device.

Richard Barrans Jr., Ph.D.



Click here to return to the Physics Archives

NEWTON is an electronic community for Science, Math, and Computer Science K-12 Educators, sponsored and operated by Argonne National Laboratory's Educational Programs, Andrew Skipor, Ph.D., Head of Educational Programs.

For assistance with NEWTON contact a System Operator (help@newton.dep.anl.gov), or at Argonne's Educational Programs

NEWTON AND ASK A SCIENTIST
Educational Programs
Building 360
9700 S. Cass Ave.
Argonne, Illinois
60439-4845, USA
Update: June 2012
Weclome To Newton

Argonne National Laboratory