Obtain the condition for bridge balance in Wheatstone΄s bridge
Answers
Answer:
When no current flows through the galvanometer it is known as the balanced condition of the galvanometer. The Wheatstone's bridge will be in the balanced condition when the current through the galvanometer is zero. Current will divide in magnitude to I1&I2 to go through resistors P and R.
Explanation:
Wheatstone's bridge: An important application of Kirchoff's law is the Wheatstone's bridge figure.
Wheatstone's network consists of resistances P, Q, R and S connected to form a closed path. A cell of emf E is connected between points A and C.
When the galvanometer shows zero deflection, the points B and D are at same potential and . Substituting in equation and .
Substituting the values of and in equation
or .
This is the condition for bridge balance. If P, Q and R are known, the resistance S can be calculated.