Does the light bulb filament appear to have a constant resistance (constant ratio of voltage to current) ?

No ... The resistance of the filament isn't constant

Explanation:

It is because the filament to light up the resistance is always constantly increasing that will ultimately causes increase in the temperature of filament and eventually it lights up. The resistance always keep on increasing as the current in the filament is going to increase and vice versa.

Does the light bulb filament appear to have a constant resistance (constant ratio of voltage to current) ?

The Answer is "NO"

The light bulb filament does not have a constant resistance.

Explanation:

Resistance is one of the basic principles of Ohm's law, resistance is the opposition to current caused by a resistor. The opposition is towards the flow of electric current. The value of resistance of a conductor depends upon: The thickness, the material from which the conductor is made, the temperature at which it operates, and, the length of the conductor.

The filament is the part of the light bulb that produces light. Filaments is a thin tungsten wire in the light bulb which resists the flow of electrons. Filament heats up when an electric current passes through it, and produces light as a result.

The resistance of the filament is not constant, rather, it increases with increased current. If extreme currents are applied to wires, they heat up, change their resistances, in turn, the resistance of a lamp increases as the temperature, and, as the current in a circuit goes up, the voltage goes up too. The relationship between the current flowing through a filament lamp and the voltage across it is not directly proportional.