Therefore, if R 1, R 2 and R 3 are known to high precision, then R x can be measured to high precision. R 2 is varied until there is no current through the galvanometer, which then reads zero.ĭetecting zero current with a galvanometer can be done to extremely high accuracy. If the bridge is unbalanced, the direction of the current indicates whether R 2 is too high or too low. If the ratio of the two resistances in the known leg (R 2/R 1) is equal to the ratio of the two in the unknown leg (R x/R 3), then the voltage between the two midpoints ( B and D) will be zero and no current will flow through the galvanometer e o. In the figure, Rx is the unknown resistance to be measured R 1, R 2 and R 3 are resistors of known resistance and the resistance of R 2 is adjustable. Wheatstone Bridge Analysis and Calculator Related Resources: Wheatstone bridge Wheatstone Bridge Analysis and Calculator
0 Comments
Leave a Reply. |