Q.

A square loop of edge length 2 m carrying a current of 2 A is placed with its edges parallel to the x-y axis. A magnetic field is passing through the x-y plane and expressed as B→=B0(1+4x)k^,  where B0=5T.. The net magnetic force experienced by the loop is ______ N.              [2024]


Ans.

(160)

B(x=0)=B0,  B(x=2)=9B0

Also, F→=iℓ→×B→

F→1=iℓB0(j^×k^)=iℓB0(i^)=2×2×5(i^)=20N(i^)

F→2=9iℓB0(-j^×k^)=9iℓB0(-i^)=2×2×45(-i^)=180N(-i^)

Fnet on AD and CB=0

F→net=F→2-F→1=160N(-i^)

⇒Fnet=160N