The potential difference (VA $$-$$ VB) between the points A and B in the given figure is
A
$$-$$ 3V
B
+3 V
C
+6 V
D
+9 V
2
NEET 2016 Phase 1
MCQ (Single Correct Answer)
+4
-1
The charge flowing through a resistance R varies with time t is Q = at $$-$$ bt2, where $$a$$ and $$b$$ are positive constants. The total heat produced in R is
A
$${{{a^3}R} \over {2b}}$$
B
$${{{a^3}R} \over {b}}$$
C
$${{{a^3}R} \over {6b}}$$
D
$${{{a^3}R} \over {3b}}$$
3
NEET 2016 Phase 1
MCQ (Single Correct Answer)
+4
-1
A potentiometer wire is 100 cm long and a constant potential difference is maintained across it. Two cells are connected in series first to support one another and then in opposite direction. The balance points are obtained at 50 cm and 10 cm from the positive end of the wire in the two cases. The ratio of emf's is
A
3 : 4
B
3 : 2
C
5 : 1
D
5 : 4
4
AIPMT 2015
MCQ (Single Correct Answer)
+4
-1
A potentiometer wire of length L and a resistance r are connected in series with a battery of e.m.f. E0 and a resistance r1. An unknown e.m.f. E is balanced at a length $$l$$ of the potentiometer wire. The e.m.f. E will be given by
