E⋅dr Here, E is constant. So, we may write above expression as VA−VB=−E⋅r VA−VB=−Er‌cos‌θ where, r is distance between points A and B, θ is angle between E and displacement vector r from point A to point B. ∴‌‌VA−VB=−10×2×cos‌60∘ (θ=60∘ from figure) =−10×2×‌