91. Two similar cells whether joined in series orin parallel have the

1.	91. Two similar cells whether joined in series orin parallel have the same current through anexternal resistanc of 2 Ω. The internalresistance of each cell is(i) 2 Ω(ii) i Ω(iv) 1.5 Ω(iii) 0.5 Ω92. When resistances are connected in parallel,the current divides itself in(i) direct ratio of resistances(ii) inverse ratio of resistances(iii) inverse ratio of potentials(iv) none of above
Answer» Let the voltage of cell be x.In Series, voltage= 2xIn Parallel,voltage= xLet Internal resistance of each be yIn series, effective internal resistance= 2yIn parallel, eff. internal resistance= y/2Now currentin both the cases In series, 2x/(2y+4)In parallel, (x)/{(y/2)+4}Both the currents are equal. So, Just check by putting the different resistances in options 92)The ratio of totalresistanceto individualresistanceis the same ratio as individual (branch)currentto totalcurrent. This is known as thecurrent dividerformula and it is a short-cut method for determining branch currents in aparallelcircuit when the totalcurrentis known.

91. Two similar cells whether joined in series orin parallel have the same current through anexternal resistanc of 2 Ω. The internalresistance of each cell is(i) 2 Ω(ii) i Ω(iv) 1.5 Ω(iii) 0.5 Ω92. When resistances are connected in parallel,the current divides itself in(i) direct ratio of resistances(ii) inverse ratio of resistances(iii) inverse ratio of potentials(iv) none of above

Answer»

Let the voltage of cell be x.In Series, voltage= 2xIn Parallel,voltage= xLet Internal resistance of each be yIn series, effective internal resistance= 2yIn parallel, eff. internal resistance= y/2Now currentin both the cases

In series, 2x/(2y+4)In parallel, (x)/{(y/2)+4}Both the currents are equal. So, Just check by putting the different resistances in options

92)The ratio of totalresistanceto individualresistanceis the same ratio as individual (branch)currentto totalcurrent. This is known as thecurrent dividerformula and it is a short-cut method for determining branch currents in aparallelcircuit when the totalcurrentis known.

Discussion

No Comment Found

Related InterviewSolutions

Reply to Comment