Crossed Electric and Magnetic fields problem

In summary: Not only is it perpendicular to the magnetic field, it is perpendicular to the direction of the velocity of the charge. Of imporatance here is that since the electric force is parallel to the electric field, and the magnetic force is perpendicuar to that, the two forces involved are perpendicular. They must be added as vectors.Got it. Thanks for your help!
  • #1
futron
12
0
"A magnetic field has a magnitude of 1.2 x 10-3 T, and an electric field has a magnitude of 5.1 x 10^3 N/C. Both fields point in the same direction. A positive 1.8 µC charge moves at a speed of 3.2 x 10^6 m/s in a direction that is perpendicular to both fields. Determine the magnitude of the net force that acts on the charge."

Using the crossed magnetic and electric field equation, wouldn't the net force be F=qE+qvB? I resolved it to 0.01609N, which isn't the correct answer. Any ideas?

~Futron
 
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  • #2
futron said:
"A magnetic field has a magnitude of 1.2 x 10-3 T, and an electric field has a magnitude of 5.1 x 10^3 N/C. Both fields point in the same direction. A positive 1.8 µC charge moves at a speed of 3.2 x 10^6 m/s in a direction that is perpendicular to both fields. Determine the magnitude of the net force that acts on the charge."

Using the crossed magnetic and electric field equation, wouldn't the net force be F=qE+qvB? I resolved it to 0.01609N, which isn't the correct answer. Any ideas?

~Futron

Did you consider the direction of the forces? I did not check your answer, but that is a likely source of error.
 
  • #3
Wouldn't Fnet be the sum if they are both pointed the same direction?

~Futron
 
  • #4
futron said:
Wouldn't Fnet be the sum if they are both pointed the same direction?

~Futron

The fields are in the same direction. Electric force is parallel to the electric field. What about the magnetic force?
 
  • #5
It is perpendicular relative to the magnetic field. How would I then calculate that into the Fnet equation? Thanks.

~Futron
 
  • #6
futron said:
It is perpendicular relative to the magnetic field. How would I then calculate that into the Fnet equation? Thanks.

~Futron

Not only is it perpendicular to the magnetic field, it is perpendicular to the direction of the velocity of the charge. Of imporatance here is that since the electric force is parallel to the electric field, and the magnetic force is perpendicuar to that, the two forces involved are perpendicular. They must be added as vectors.
 
  • #7
Got it. Thanks for your help!

~Futron
 

What is the "Crossed Electric and Magnetic fields problem"?

The "Crossed Electric and Magnetic fields problem" is a physics problem that involves the interaction between an electric field and a magnetic field. This problem is often encountered in electromagnetism and can be solved using equations such as the Lorentz force law.

What are the main factors that affect the behavior of charged particles in crossed electric and magnetic fields?

The main factors that affect the behavior of charged particles in crossed electric and magnetic fields are the strength and orientation of the electric and magnetic fields, as well as the velocity of the charged particle.

How do crossed electric and magnetic fields affect the motion of a charged particle?

The motion of a charged particle in crossed electric and magnetic fields is affected by the Lorentz force, which causes the particle to experience a force perpendicular to both the electric and magnetic fields. This can result in the particle moving in a circular or helical path, depending on the initial conditions.

What are some real-life applications of the "Crossed Electric and Magnetic fields problem"?

The "Crossed Electric and Magnetic fields problem" has many real-life applications, such as in particle accelerators, mass spectrometers, and cathode ray tubes. It is also used in various technologies, including magnetic levitation trains and particle beam therapy for cancer treatment.

What are some common misconceptions about crossed electric and magnetic fields?

One common misconception is that crossed electric and magnetic fields can cancel each other out. In reality, the two fields interact and can result in a complex motion for charged particles. Another misconception is that only charged particles can be affected by these fields, when in fact, they can also affect neutral particles indirectly through the creation of electric and magnetic fields.

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