Three wire rows show field size changing force magnitude and current direction changing only the finite force direction.
Magnetic wire force changes with field and finite direction. Exact arithmetic here means exact results for the stated model inputs; measured inputs still carry uncertainty and significant-figure limits.
highlighted = computed this step
One tesla gives eight newtons
Field 1 T, current 2 A, and length 4 m give force 8 N with direction up.
F=1×2×4=8
Doubling field doubles the force
Field 2 T, current 2 A, and length 4 m give force 16 N with direction up.
F=2×2×4=16
Reversing current flips direction, not size
Field 2 T, current 2 A, and length 4 m give force 16 N with direction down.