Question

Answer this easy circuit problem

Answer 1

if R2 was open circuited, what is the reading in the voltmeter?

Answer 2

please note voltage V_2 on R2, if (R2 is not an open circuit) is:
\[V _{2}=\frac{ E }{ 1+\frac{ R _{1} +R _{3}+R _{4}}{ R _{2} } }\]
now considering open circuit condition, namely
R_2--->+infinity, we can write:
\[V _{2}=E\]
where E=200 Volts