The ac losses are investigated on the Ag‐sheathed (Bi,Pb)2Sr2Ca2Cu3Oxsuperconducting wires in the rod and tape forms through an ac transport method and an ac magnetic method at 77 K. Experimental results show that the ac losses at 50 Hz for both rod and tape samples are mainly dominated by the hysteresis loss independent of the measuring method. However, the tape sample yields ac transport losses larger than the ac magnetic losses by about one order of magnitude, while the rod sample shows no difference between them. This discrepancy is explained by the difference in the geometry between both samples, which affects only the ac magnetic losses. ©1995 American Institute of Physics.