A block is sliding on a (near) frictionless plane with incline angle 45°. Which force is greater in magnitude, the net force acting on the block or the normal force acting on the block

The force acting on the block along the plane = mg Sin 45 = 0.707 x mg

The normal force acting on the block = mg Cos 45 = 0.707 x mg

Here, both the forces are equal in magnitude and the direction is different.

The net force is acting along the plane and the normal force is acting perpendicular to the plane.