copper coil, when connected to a 30-volt supply, initially takes a current of 3 A and has a mean temperature of 20 C°. After some time, the coil's current falls to 2.85 A while the supply voltage remains the same. The mean temperature of the coil is then 33.4 Cº. Determine the temperature coefficient of resistance at 0 Cº.

copper coil, when connected to a 30-volt supply, initially takes a current of 3 A and has a mean temperature of 20 C°. After some time, the coil's current falls to 2.85 A while the supply voltage remains the same. The mean temperature of the coil is then 33.4 Cº. Determine the temperature coefficient of resistance at 0 Cº.

Delmar's Standard Textbook Of Electricity

7th Edition

ISBN:9781337900348

Author:Stephen L. Herman

Publisher:Stephen L. Herman

Chapter32: Three-phase Motors

Section: Chapter Questions

Problem 8RQ

See similar textbooks

Similar questions

For figure (1)draw and calculate the voltages waveform across each half of secondary winding and across load when 100sin2π60t applied across the primary, then find PIV.
A coil has a time constant of 1 second and an inductance of 10 H. What is the value of the current 0.1 second after switching on to a steady voltage of 100 volts?
What is the effect on induced voltage of adding more turns of wire to a coil
A triangle waveform with following specifications in Table B1. Table B1 RMS Voltage 50mV Number of cycles/second 100 i) Sketch the approximate triangular waveform with all specifications. ii) A transformer has primary coil with 100 turns and secondary coil with 120 turns. Estimate the current in the secondary coil, If the current in the primary coil is 4 Ampere
6. A copper coil has a resistance of 200 ohms temperature is 0 degree centigrade. Calculate the resistance of the coil when its mean when its mean temperature is 80 degree centigrade. Temperature coefficient of copper is 0.004041 centigrade
6. A copper coil has a resistance of 200 ohms when its mean temperature is s 0 degree centigrade. Calculate the resistance of the coil when its mean temperature is 80 degree centigrade. Temperature coefficient of copper is 0.004041 centigrade1
AC xuf lac V ac 21. The simple AC powered circuit above is being measured for AC current and voltage across a 1uF capacitor. The measured current is 200mA and the measured voltage is 40V. (note: 2 separate questions follow) a. Calculate the capacitive reactance, Xc. b. Calculate the voltage frequency.
A relay has 12 ohms resistance, and a 2.4 H inductance is suddenly switched across 120 volts supply of negligible internal resistance. Determine the instantaneous current after 0.1 second.Ans 3.9
Please answer the problem below. Give the waveform for the current of a 10-mH coil if the voltage acrossthe coil follows the pattern of the figure below if t = 0s and the curren IL = 4 mA
DC-AC Circuits Approximately, how long does it take the circuit to have a current near 5A upon closing of the switch? 5V 5H O A. 25 seconds B. 5 seconds O C. 1 second D. O second O E. 0.2 seconds
A magnatic flux of 6 Wb-turn sets up in the coil, when a current of 3 A flows through it. What is the inductance (in H) of the coil ?
For the figure shown below if the current is moving clockwise around the coil. Which direction does the coil rotate? S O The whole coil moves down. The whole coil moves up. The right side goes down, and the left side goes up. The right side goes up, and the left side goes down.