Seven resistances are connected as shown in the figure. The equivalent resistance between $A$ and $B$ is ............... $\Omega$
A$3$
B$4$
C$4.5$
D$5$
Medium
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B$4$
b (b) The given circuit can be simplified as follows
So, ${R_{AB}} = \frac{{8 \times 8}}{{8 + 8}} = \frac{{64}}{{16}} = 4\Omega $
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A rod of a certain metal is $1.0\, m$ long and $0.6\, cm$ in diameter. Its resistance is $3.0 × {10^{ - 3}}\, ohm$. Another disc made of the same metal is $2.0\, cm$ in diameter and $1.0\, mm$ thick. What is the resistance between the round faces of the disc
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