A transformer core with an effective mean path length of 10 in has a 300-turn coil wrapped around one leg. Its cross-sectional area is 0.25 in2, and its magnetization curve is shown below. If current of 0.25 A is flowing in the coil, what is the total flux in the core? What is the flux density? 3. 28 26 24 22 20 1.6 14 12 06 04 02 10 20 30 40 50 100 200 300 s00 1000 2000 5000 Magnetizing intensity H.A-tumsm [1.27 T, 0.000205 Wb] Flux demity, T

In the core of a long solenoid the magnetic flux density is 100 Tesla. The cross section of the solenoid is a circle with diameter d=10 cm. Determine the magnetic flux in the core in mWb.

Problem 3 A core with three legs is shown in the figure. Its depth is 5 cm, and there are 200 turns on the left most leg.100 turns on the right most leg. The relative permeability of the core can be assumed 1500 and constant. + 15 cm- 25 cm 25 om 2A 200 tums 004 cm 25 an What flux exists in each of the three legs of the core? What is the flux density in each of the legs?

A transformer has primary and secondary turns of 1250 and 125 respectively. It has core cross-sectionof 36 cm2 and its rms flux density is to be limited to 1.4 T (to prevent core saturation). Whatmaximum 50 Hz voltage can be applied on the primary side and the corresponding open-circuitsecondary voltage?The core has a mean length of 150 cm and its relative permeability can be assumed to be 8000. Whatwould be the rms exciting current when the transformer’s primary winding is excited at a voltage ascalculated above? Also calculate the magnetizing susceptance as seen from primary and secondarysides.If the transformer were to be excited at 60 Hz, 1. What should be the maximum primary voltage for thecore flux density limit not to be exceeded? 2. What would be the magnetizing susceptance as seen oneach side in this case?

A single phase 60 Hz transformer has its core volume of 1.5x10-3 cu m. The maximum flux density is 1.0 tesla and the hysteresis constant of the core is 6000. find the hysteresis loss.

Which of the following are power losses that can occur in a practical transformer (non-ideal)? copper loss O loss due to eddy currents V hysteresis loss O voltage drop due to coil material

100 W ans

You have a solenoid with an into all current of 577A and a turn dentistry of 6601 loops/m What is the intial magnetic field through the solenoid ? the current in the solenoid drops to 34 A over the course of 4ms. What is the final magetic field through the solenoid ? the coil has a resistance of 20. What is the current though the coil? what is the power disssipated by the coil? inside the solenoid 56loops and a radius of 6.2cm. What is the magnitude of the induced in the 56 turn coil. Positive nunber

There is 50 mA of current through a coil with 250 turns. The flux is 150 µWb. What is the mmf? What is the reluctance of the circuit?     A. Fm = 1.25 At   -   R=4.3x10-3 At/Wb   B. Fm = 2.25 At   -   R=8.3x10-3 At/Wb   C. Fm = 1.25 At   -   R=8.3x10-3 At/Wb   D. Fm = 1.25 At   -   R=8.3x10-2 At/Wb

3. The maximum flux density in the core of 240/2400 V, 50 Hz, single phase transformer is 1 Wb/m² if the e.m.f. per turn is 8 V, the area of the core is a) 0.132 b) 0.086 c) 0.241 d) 0.036 (125 mark)