Question:
A charged particle is moving parallel to a uniform magnetic field. Then the force on the charged particle is
A charged particle is moving parallel to a uniform magnetic field. Then the force on the charged particle is
Show Hint
Magnetic force is maximum when
\[
\theta=90^\circ,
\]
for which
\[
F=qvB.
\]
If the particle moves parallel or antiparallel to the magnetic field,
\[
\theta=0^\circ \text{ or }180^\circ,
\]
and hence
\[
F=0.
\]
Updated On: Jul 29, 2026
- \[ qvB \]
- \[ \frac{B}{qv} \]
- \[ \frac{v^2B}{q} \]
- Zero
Show Solution
Verified By Collegedunia
The Correct Option is D
Solution and Explanation
Concept:
The magnetic force acting on a charged particle moving in a magnetic field is given by
\[
F=qvB\sin\theta,
\]
where
\[
q=\text{charge},
\qquad
v=\text{velocity},
\qquad
B=\text{magnetic field},
\]
and \(\theta\) is the angle between \(\vec v\) and \(\vec B\).
Step 1: Identify the angle between velocity and magnetic field. The particle moves parallel to the magnetic field. Therefore, \[ \theta=0^\circ. \]
Step 2: Substitute into the magnetic force equation. \[ F=qvB\sin0^\circ. \] Since \[ \sin0^\circ=0, \] \[ F=0. \]
Step 3: State the result. No magnetic force acts on a charged particle moving parallel (or antiparallel) to the magnetic field. \[ \boxed{F=0} \] \[ \boxed{\text{Answer = (D)}} \]
Step 1: Identify the angle between velocity and magnetic field. The particle moves parallel to the magnetic field. Therefore, \[ \theta=0^\circ. \]
Step 2: Substitute into the magnetic force equation. \[ F=qvB\sin0^\circ. \] Since \[ \sin0^\circ=0, \] \[ F=0. \]
Step 3: State the result. No magnetic force acts on a charged particle moving parallel (or antiparallel) to the magnetic field. \[ \boxed{F=0} \] \[ \boxed{\text{Answer = (D)}} \]
Was this answer helpful?
0
0
Top AP EAPCET Physics Questions
- A body is projected from the ground at an angle of $\tan^{-1} \left( \frac{8}{7}\right)$ with the horizontal. The ratio of the maximum height attained by it to its range is
- A lens forms real and virtual images of an object, when the object is at $u_{1}$ and $u_{2}$ distances respectively. If the size of the virtual image is double that of the real image, then the focal length of the lens is (take, the magnification of the real image as $m$ )
- Two spheres $P$ and $Q$, each of mass $200\, g$ are attached to a string of length one metre as shown in the figure. The string and the spheres are then whirled in a horizontal circle about $O$ at a constant angular speed. The ratio of the tension in the string between $P$ and $Q$ to that of between $P$ and $O$ is $(P$ is at mid-point of the line joining $O$ and $Q$ )
- The radii of the two columns in a U - tube are r1 and r2. When a liquid of density p (angle of contact is $ 0{}^\circ $ ) is filled in it, the level difference of the liquid in the two arms is h. The surface tension of the liquid is: (g = acceleration due to gravity)
- A rigid metallic sphere is spinning around its own axis in the absence of external torque. If the temperature is raised, its volume increases by $9 \%$. The change in its angular speed is
View More Questions
Top AP EAPCET Magnetic Force Questions
- An electron moving along positive x-direction with velocity \( 2 \times 10^5 \) ms\(^{-1}\) enters a magnetic field of \( \vec{B} = \hat{i} + 4 \hat{j} + 3 \hat{k} \) T. The magnitude of the force acting on the electron is:
- A magnetic field of 1 T is acting on a wire carrying a current of 1 A so that the wire is at rest in air. If the mass of the wire is 100 g, then the length of the wire is:
- An isosceles triangular current-carrying loop is kept perpendicularly in a uniform magnetic field \( \vec{B}_0 \) as shown in the figure. The force on the loop due to magnetic field is:
- A charged particle is moving in a uniform magnetic field and enters a lead layer, losing half of its kinetic energy. The radius of curvature of its path becomes:
- The magnetic force \( q [v \times B] \) is
View More Questions
Top AP EAPCET Questions
- A body is projected from the ground at an angle of $\tan^{-1} \left( \frac{8}{7}\right)$ with the horizontal. The ratio of the maximum height attained by it to its range is
- The four quantum numbers of the valence electron of potassium are :
- A lens forms real and virtual images of an object, when the object is at $u_{1}$ and $u_{2}$ distances respectively. If the size of the virtual image is double that of the real image, then the focal length of the lens is (take, the magnification of the real image as $m$ )
- Two spheres $P$ and $Q$, each of mass $200\, g$ are attached to a string of length one metre as shown in the figure. The string and the spheres are then whirled in a horizontal circle about $O$ at a constant angular speed. The ratio of the tension in the string between $P$ and $Q$ to that of between $P$ and $O$ is $(P$ is at mid-point of the line joining $O$ and $Q$ )
- The volume of $0.02\, M$ acidified permanganate solution required for complete reaction of $60\, mL$ of $0.01\, MI^{-}$ ion solution to form $I_2$ in $mL$ is
View More Questions