Question

A straight vertical conductor carries a current. At a point 5 cm due north of it, the magnetic induction is found to be $20\,\mu T$ due east. The magnetic induction at a point 10 cm east of it will be

• A. $5\mu T \,north$
• B. $10\mu T \,north$
• C. $5\mu T \,south$
• D. $10\mu T \,south$

Answer 1

Answer: (D)

$10\mu T \,south$

Answer 2

Given:
Magnetic induction $B_1 = 20 \, \mu T$ due east at a point 5 cm due north of the conductor.
- We need to find the magnetic induction $B_2$ at a point 10 cm east of the conductor.

Identify the Given Magnetic Field:
$B_1 = 20 \, \mu T$ due east at a point 5 cm due north of the conductor.

Direction of the Current:
The magnetic field $B_1$ is eastward, which typically corresponds to a current flowing downward (along the negative z-axis) for a vertical conductor.

Magnetic Induction at 10 cm East:
At a point 10 cm east of the conductor, the magnetic induction $B_2$ will have the same horizontal component as $B_1$ because we are in the same horizontal plane of the conductor's magnetic field.
Therefore, the magnetic induction $B_2$ at a point 10 cm east of the conductor will be $10 \, \mu T$ due south.

So, the correct option is (D): $10 \, \mu T$ south