The potential difference across a, b is mathematically given as
E_a=0.5
E_b= 0
Generally the equation for the switch when closed is mathematically given as
[tex]Rc=Ra+\frac{Rb}{2}[/tex]
Therefore
Rc=3R/2
Where
[tex]va=2R/3R *e[/tex]
va=2/3* e
vb=vc=(2/3e)
When switch is closed
va=e
vb=vc=0
Therefore potential difference across a is
[tex]E_a=\frac{e-2/3e}{2/3e}[/tex]
E_a=1/2
E_a=0.5
And potential difference across b is
E_b= 0
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