Electric field direction between charged plates

Steps:

• Electric potential is higher at the +400V plate than at the -400V plate.
• The electric field points from the region of higher potential to lower potential.
• For parallel plates, the field is uniform and directed perpendicularly from the positive plate to the negative plate.
• Assuming +400V plate on the left and -400V on the right, field arrows point rightward.

Why A is correct:

• Arrows →→→ show field directed from +400V (high potential) to -400V (low potential), matching the definition that E = -∇V (field opposes potential gradient).

Why the others are wrong:

• B: Arrows ←←← point from -400V to +400V, reversing the direction from low to high potential.
• C: Starts with -400V on left and +400V on right with →→→, so arrows point from low to high potential.
• D: Starts with -400V on left and +400V on right with ←←←, so arrows point toward low potential but setup has positive on right.

Final answer: A