\(\vec{B}=B_0\left(1+\frac{x}{l}\right) \hat{k}\)
\(\text { at } x=0, B_1=B_0 \hat{k}\)
\(\text { at } x=l, B_2=2 B_0 \hat{k}\)
\(F_{\text {net }}=F_2-F_1=i l\left(B_2-B_1\right)\)
\(=i l\left(2 B_0-B_0\right)\)
\(=ilB_0\)
(પ્રોટોનનું દળ $=1.67 \times 10^{-27}\, kg$, પ્રોટોનનો વિજભાર $=1.69 \times 10^{-19}\,C$)