A coil of wire is kept in melting ice . Its resistance measured by a Wheatstone bridge is 5Omega . If the coil is heated to 100^(@)C and another wire of resistance 100Omega is coonnected in parallel to it , the balanced condition of the brige remains unchaged . Determine the temperature coefficient of resistance of the wire of the coil .

A null point is obtained when two resistors , of resistance r each, are connected in series and placed in the fourth arm of a wheatstone bridge . Now , the resistance R of the third arm is kept fixed ,and r, connected in parallel, are placed in the fourth arm. then a null point is obtained only by interchanging the resistances P and Q , and also the value of r.

A Wheatstone bridge has the resistances 10Omega,10Omega,10Omega and 30Omega in its four arms. What resistance joined in parallel to the 30 resistance will bring it to the balanced condition?

Equivalent resistance are 12Omega and 2.25Omega when two resistors are connected in series and parallel. Calculate the value of resistors.

A galvanometer together with an unknown resistance in series is connected across two identical batteries of each 1.5V When the batteries are connected in series, the galvanometer records a current of 1A and when the batteries are connected in parallel, the current is 0.6A. What is the internal resistance of the battery ?

In a Wheatstone bridge a resistance S is fixed in fourth arm . Keeping resistance R_(1) in third arm null condition is obtained . Now if the resistance P and Q are interchanged , resistance R_(1) has to be replaced by R_(2) to get the balance condition agian . Find the ratio of P and Q and also the value os S .

The resistance in the three arms of a Wheatstone bridge are repectively 15Omega , 10Omega and 22.5Omega. when a copper coil is placed in the fourth arm of the bridge at 0^(@)C the bridge ramains balanced . But to restore the balance of the bridge at 50^(@)C of the coil temperature an additinal resistance r has to be arranged in parallel with the coil . What is the value or ? (temperture cofficient of resistance of copper =0.00425^(@)C^(-1)

A currrent of 0.1 A enters a Wheatstone bridge from a source of the electricity . The resistance of each of the first three arms of the bridge is 10Omega and the resistance of its fourth arm is 20Omega . If the resistance of the galvanometer be 100Omega what will be the galvanometer current ?

R_1 and R_2 are two resistances they are connected in parallel combinations Write down their equivalent resistance in each case.