Question 629 of 949
A charged particle with a charge of +2 ยตC is moving at a velocity of 5 m/s perpendicular to a magnetic field of strength 0.1 T. What is the magnitude of the magnetic force experienced by the particle?
Correct Answer:
C
Explanation
To determine the magnitude of the magnetic force experienced by a charged particle moving in a magnetic field, we can use the formula for the magnetic force \( F \) on a charged particle:
\[
F = q \cdot v \cdot B \cdot \sin(\theta)
\]
Where:
- \( F \) is the magnetic force (in Newtons, N)
- \( q \) is the charge of the particle (in Coulombs, C)
- \( v \) is the velocity of the particle (in meters per second, m/s)
- \( B \) is the magnetic field strength (in Teslas, T)
- \( \theta \) is the angle between the velocity vector and the magnetic field vector
### Step-by-Step Calculation
1. **Identify the given values:**
- Charge \( q = +2 \, \mu C = 2 \times 10^{-6} \, C \)
- Velocity \( v = 5 \, m/s \)
- Magnetic field strength \( B = 0.1 \, T \)
- Since the particle is moving perpendicular to the magnetic field, the angle \( \theta = 90^\circ \).
2. **Calculate \( \sin(\theta) \):**
- For \( \theta = 90^\circ \), \( \sin(90^\circ) = 1 \).
3. **Substitute the values into the formula:**
\[
F = (2 \times 10^{-6} \, C) \cdot (5 \, m/s) \cdot (0.1 \, T) \cdot 1
\]
4. **Perform the multiplication:**
\[
F = 2 \times 10^{-6} \cdot 5 \cdot 0.1
\]
\[
F = 2 \times 5 \times 0.1 \times 10^{-6}
\]
\[
F = 10 \times 0.1 \times 10^{-6}
\]
\[
F = 1 \times 10^{-6} \, N
\]
\[
F = 0.00001 \, N = 0.01 \, N
\]
### Conclusion
The magnitude of the magnetic force experienced by the particle is **0.01 N**. Therefore, the correct option is **A**.
### Explanation of Other Options
- **Option B (0.1 N)**: This value is too high based on the calculations. It would imply a much larger force than what is produced by the given charge, velocity, and magnetic field.
- **Option C (0.2 N)**: This is also incorrect. It suggests a force that is double the calculated value, which does not align with the parameters provided.
- **Option D (0.5 N)**: This option is significantly higher than the calculated force and does not correspond to the values given in the problem.
### Common Pitfalls
- **Forgetting to convert units**: Always ensure that the charge is in Coulombs, velocity in m/s, and magnetic field strength in Teslas.
- **Misunderstanding the angle**: Remember that the sine function is crucial when the angle is not 90 degrees. In this case, since the motion is perpendicular, it simplifies the calculation.
- **Neglecting the direction of the force**: While this question asks for magnitude, it's important to remember that the direction of the force is given by the right-hand rule.
### Revision Summary
- Use the formula \( F = q \cdot v \cdot B \cdot \sin(\theta) \) to calculate magnetic force.
- Ensure all units are consistent (C, m/s, T).
- Remember that \( \sin(90^\circ) = 1 \) when the velocity is perpendicular to the magnetic field.
- Check calculations carefully to avoid common errors in unit conversion and angle interpretation.