A potentiometer experiment is set up to compare the e.m.f.s E1, and E2, of two cells. When the null point is obtained, the current is drawn from________
A. only the driver cell
B. only the cell of e.m.f. E1
C. only the cell of e.m.f. E2
D. both the driver cell and the cells of e.m.f.s E1, and E2
Answer:A
A potentiometer experiment is set up to compare the e.m.f.s E1, and E2, of two cells. When the null point is obtained, the current is drawn from________
A. only the driver cell B. only the cell of e.m.f. E1 C. only the cell of e.m.f. E2 D. both the driver cell and the cells of e.m.f.s E1, and E2