Magnetic Effects Of Current And Magnetism

The magnetic field at the centre of a circular loop of radius carrying a current is given by the formula: where:
- is the magnetic field at the centre of the loop,
- is the permeability of free space ( ),
- is the current, and
- is the radius of the loop.
Step 1: Rearrange the formula to solve for current.
Rearrange the equation to solve for the current :
Step 2: Substitute the given values.
We are given:
- ,
- ,
- .
Substitute these values into the equation: Thus, the current through the loop is:

Step 1: Understanding the Concept:
When a current-carrying conductor is placed in an external magnetic field, it experiences a magnetic force. This is the fundamental principle behind electric motors.
Step 2: Key Formula or Approach:
The magnitude of the magnetic force on a straight current-carrying conductor is given by the formula:

Where:
= Magnetic force
= Current
= Length of the conductor in the field
= Magnetic field strength
= Angle between the direction of current and the magnetic field.
When the angle is not explicitly specified in such problems, standard practice is to assume maximum force, meaning the conductor is placed perpendicular to the field ( , ).
Step 3: Detailed Explanation:
Given values:
Length, m
Current, A
Magnetic field, T
Assuming perpendicular orientation ( ):



Step 4: Final Answer:
The force acting on the conductor is 0.4 N.