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ACTIVITY NO. 7, VARIATION OF POTENTIAL DROP WITH LENGTH OF Wirg, , Aim: To study the variation in potential drop with length of a wire for a steady current,, , Apparatus : Potentiometer, battery (or driving cell), plug key, voltmeter, rheostat, Jockey, connecting wires., , Circuit diagram :, , , , , , , , , , , , , , , , , , , , , , , , , , - _ ~\, + " A 7 P, E.—. ——, ct B e, lable:cE - cee battev, ME ait og, RA- -\odk, Y= voltemekev Px) ) 7, , , , Formula: For a potentiometer wire of uniform density and cross-sectional area carrying a, steady current, potential drop (V) is proportional to length (£) of the wire., Potential gradient k = V/£, , Procedure :, 1. Arrange and connect the circuit as shown in the circuit diagram Close the key K., , 2. Touch the jockey at length 60 cm of the wire from end A. Note down the voltmeter reading., , 3. Touch the jockey at different length such as, 120 cm, 180cm, 240cm of the wire from end A, and note the voltmeter reading in each case., , , , , , , , , , , , , , , , , , , , Observations :, Least count of voltmeter = ------- Vv, ‘Ob. No. | Length of potentiometer Voltmeter Reading ~, wire ‘f ‘em °V? volt Ratio —— V/em, : £, 1 So 6°22. oar, 4 ee o"4 07004, 3 \So O-€ ee, , >canneg witn Vamscann