The power adapters of devices we use contain transformers. In one such adapter, the input to the transformer draws 1.8 A current when connected to the 120 Volt plug-point in our walls. The adapter/transformer is designed to output 5.0 A current. The input to the transformer (or primary) has a coil with 50 turns. a. What voltage is the output (secondary) providing? b. How many turns does the coil in the secondary (output) have? c. Suppose you know that the speed at which light can travel through a material is 2.5 × 10 m/s and that the magnetic permeability (u) of the material is 10-0 T.m/A. What is the electrical permittivity (e) of this material? [It is possible to answer this part without knowing how to answer parts (a) and (b). In fact, this question has nothing to do with "transformers".]

The power adapters of devices we use contain transformers. In one such adapter, the input to the transformer draws 1.8 A current when connected to the 120 Volt plug-point in our walls. The adapter/transformer is designed to output 5.0 A current. The input to the transformer (or primary) has a coil with 50 turns. a. What voltage is the output (secondary) providing? b. How many turns does the coil in the secondary (output) have? c. Suppose you know that the speed at which light can travel through a material is 2.5 × 10 m/s and that the magnetic permeability (u) of the material is 10-0 T.m/A. What is the electrical permittivity (e) of this material? [It is possible to answer this part without knowing how to answer parts (a) and (b). In fact, this question has nothing to do with "transformers".]

University Physics Volume 2

18th Edition

ISBN:9781938168161

Author:OpenStax

Publisher:OpenStax

Chapter15: Alternating-current Circuits

Section: Chapter Questions

Problem 48P: A transformer is used to supply a 12-V model train with power from a 110-V wall plug. The train...

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