# Two short bar magnets of length $1 mathrm{~cm}$ each have magnetic moments

Question:

Two short bar magnets of length $1 \mathrm{~cm}$ each have magnetic moments $1.20 \mathrm{Am}^{2}$ and $1.00 \mathrm{Am}^{2}$ respectively. They are placed on a horizontal table parallel to each other with their $\mathrm{N}$ poles pointing towards the South. They have a common magnetic equator and are separated by a distance of $20.0$ $\mathrm{cm}$. The value of the resultant horizontal magnetic induction at the midpoint $\mathrm{O}$ of the line joining their centres is close to:-

(Horizontal component of earth's magnetic induction is $3.6 \times 10^{-5} \mathrm{~Wb} / \mathrm{m}^{2}$ )

1. $3.6 \times 10^{-5} \mathrm{~Wb} / \mathrm{m}^{2}$

2. $2.56 \times 10^{-4} \mathrm{~Wb} / \mathrm{m}^{2}$

3. $3.50 \times 10^{-4} \mathrm{~Wb} / \mathrm{m}^{2}$

4. $5.80 \times 10^{-4} \mathrm{~Wb} / \mathrm{m}^{2}$

Correct Option: , 2

Solution: