Saved Bookmarks
| 1. |
The value of resistance of an unknown resistor is calculated using the formula `R = V//I ` where V and I are the readings of the voltmeter and the ammeter, respectivley. Consider the circuits below. The internal resistances of the voltmeter and the ammeter `(R_V and R_G, respectively)` are finite and nonzero. , Let `R_(A) and R_(B)` be the calculated values in the two cases A and B , respectively. The relation between `R_A` and the actual value of R isA. `RgtR_(A)`B. `RltR_(A)`C. `R=R_(B)`D. dependent upon E and r. |
|
Answer» Correct Answer - A a. `R_(A) = R_(A) = (R xx R_V)/(R+R_V) ltR` `R_(B) = R+R_0 gtR` (Tough) % error in case A. `(R_(A)-R)/R xx 100 = (R_(V)/(R+R_(V)) -1) xx 100 ` `R/(R+R_(V)) xx 100 - 1%` Percentage error in case B `(R_(B) - R)/R xx 100 = R_(G)/R xx 100 = 10%` Hence, percentage error in circuit B is more than that in A. |
|