Question

Path of charged particle entering in uniform magnetic field at an angle \( 60^\circ \) is:

• A. Straight line
• B. Helical
• C. Parabola
• D. Circular

Hint:

When a charged particle moves at an angle to the magnetic field, the path it follows is helical, combining circular motion and linear motion along the field.

Answer 1

The Correct Option is B

Step 1: Understanding the concept.
When a charged particle enters a uniform magnetic field at an angle (other than 90°), it will follow a helical path due to the combination of uniform circular motion in the plane perpendicular to the magnetic field and linear motion along the direction of the field.
Step 2: Analyzing the options.
(1) Straight line: This is incorrect. A straight line path would occur if the charge moved parallel to the magnetic field.
(2) Helical: Correct. The motion is helical because the particle moves in a spiral due to the component of velocity perpendicular to the field.
(3) Parabola: This is incorrect. A parabolic path would occur for projectile motion under gravity, not in a magnetic field.
(4) Circular: This is incorrect. Circular motion occurs when the velocity is perpendicular to the magnetic field, but here the velocity has a component along the field.
Step 3: Conclusion.
The correct answer is (2) Helical, as the particle follows a helical path due to the magnetic force acting perpendicular to the velocity.