Q.

Electric field in a region is given by E→=Axi^+Byj^, where A=10 V/m2 and B=5 V/m2. If the electric potential at a point (10, 20) is 500 V, then the electric potential at the origin is ________ V.                [2026]

1 1000  
2 0  
3 500  
4 2000  

Ans.

(4)

E→=10x i^+5y j^

Vat(10,20)=500 V

ΔV=-∫E→·dr→

500-V0=-∫(0,0)(10,20)(10x i^+5y j^)·(dx i^+dy j^)

500-V0=-[5x2+5y22](0,0)(10,20)

V0-500=(500+5×4002)-(0-0)

V0-500=500+1000

V0=2000 V