2Ω. Based on the graph the resistance of the bulb is 2Ω.
Based on the graph of the image we can see there are a linear proportionality between the voltage and the current. So, we can modeling this problem calculating the slope of the straight line in the graph as follow:
We can write a formula of the form [tex]m=\frac{y_{1}-y }{x_{1}-x}[/tex].
From the Ohm's Law we know that the resistance is directly proportional to the voltage and inversely proportional to the current [tex]R = \frac{V}{I}[/tex].
From the graph we can see in the x-axis the values of the voltage and the y-axis the value of the current, with the points (x, y) = (2, 1) and (x₁, y₁) = (4, 2) marked in the graph, we can write:
[tex]m=\frac{y_{1}-y }{x_{1}-x}[/tex]
[tex]m=\frac{2A - 1A}{4V - 2V}[/tex]
We need to express the equation [tex]m=\frac{2A - 1A}{4V - 2V}[/tex] in the form [tex]R = \frac{V}{I}[/tex]:
[tex]R = \frac{1}{m}=\frac{1}{\frac{2A - 1A}{4V - 2V}} \\R = \frac{4V - 2V}{2A - 1A}}\\R = \frac{2V}{1A}[/tex]
R = 2Ω
