A) \[R={{R}_{2}}-{{R}_{1}}\]
B) \[R={{R}_{2}}\times \left( {{R}_{1}}+{{R}_{2}} \right)/\left( {{R}_{2}}-{{R}_{1}} \right)\]
C) \[R={{R}_{1}}{{R}_{2}}/\left( {{R}_{2}}-{{R}_{1}} \right)\]
D) \[R={{R}_{1}}{{R}_{2}}/\left( {{R}_{1}}-{{R}_{2}} \right)\]
Correct Answer: C
Solution :
[c] \[I=\frac{2\varepsilon }{R+{{R}_{1}}+{{R}_{2}}}\] Pot. difference across second cell \[=V=\varepsilon -I{{R}_{2}}=0\] \[\varepsilon =\frac{2\varepsilon }{R+{{R}_{1}}+{{R}_{2}}}.{{R}_{2}}=0\] \[R+{{R}_{1}}+{{R}_{2}}-2{{R}_{2}}=0\] \[R+{{R}_{1}}-{{R}_{2}}=0\text{ }\therefore R={{R}_{2}}-{{R}_{1}}\]
You need to login to perform this action.
You will be redirected in
3 sec
