A uniform electric field and a uniform magnetic field exist in a region in the same direction. An electron is projected with a velocity pointed in the same direction. The electron will:
Correct answer: D. Keep moving in the same direction but its speed will decrease
- A. Turn to its right
- B. Turn to its left
- C. Keep moving in the same direction but its speed will increase
- D. Keep moving in the same direction but its speed will decrease
Explanation
The magnetic force will be zero because the electron's velocity is parallel to the magnetic field. The electric force on the negatively charged electron will be opposite to the direction of the electric field, thus opposing its motion and causing it to slow down (decrease its speed).
Report an error
The more specific you are, the faster it gets fixed. A source beats an opinion.
Prefer email? [email protected]
About Electromagnetism
Magnetic flux density and magnetic flux describe the strength of a magnetic field and the field passing through a surface. A charged particle moving through a magnetic field experiences a force perpendicular to its velocity and may follow circular or helical motion, depending on the angle between velocity and field.
Practise Electromagnetism
1,176 free Electromagnetism MCQs from Physics, each with the correct answer and an explanation. Unlimited attempts, no account needed.
Discussion
Stuck on an option, or know a faster way to get there? Ask or explain it here.
No comments yet. Be the first to explain this one.
Exams that ask Physics questions like this
Physics is on 16 papers prepared for on TestUstad, and all of them draw the same bank, so this question is worth knowing for every one of them.
More Electromagnetism questions
The magnetic field due to the electric current in a conducting straight wire is:
The magnetic field produced due to the current in a straight wire is proportional to the:
An "α" particle enters a magnetic field of strength "B" with a speed "v" parallel to the direction of the magnetic field. The force on the particle is:
Which of the following does not affect the motion of a moving electron?
A current of 2A is passing through an inductor of 2mH. Energy stored by it is:
The radius of curvature of the path of a charged particle moving in a static uniform magnetic field is: