Need help with two questions, dealing with electricity

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SUMMARY

This discussion addresses two electrical engineering problems involving Nichrome wire and a light bulb. The first question requires calculating the length of Nichrome wire needed for a heater operating at 400 W and 120 V, using the formula P = V²/R. The second question involves analyzing a light bulb's current, defined by I = (0.707 A)sin[(314 Hz)t], to determine the frequency of the alternating current, the resistance of the filament, and the average power delivered to the bulb.

PREREQUISITES
  • Understanding of Ohm's Law and power calculations (P = V²/R)
  • Familiarity with AC circuit analysis and sinusoidal functions
  • Knowledge of electrical resistance and its relation to wire dimensions
  • Basic concepts of frequency in alternating current (AC) systems
NEXT STEPS
  • Calculate the length of Nichrome wire using the resistance formula R = ρ(L/A)
  • Learn about the relationship between current, voltage, and power in AC circuits
  • Explore the concept of average power in AC systems and its calculation
  • Study the effects of temperature on resistance in conductive materials
USEFUL FOR

Electrical engineering students, educators, and professionals dealing with circuit design and analysis, particularly those focusing on heating elements and AC power systems.

Marcelgluch
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Hi, i have two questions from my assignment that i am having a very hard time understanding...

1. A piece of Nichrome wire has a radius of 6.5x10^-4 m. It is used in a laboratory to make a heater that uses 4.00x10^2 W of power when connected to a voltage source of 120 V. Ignoring the effect of temperature on resistance, estimate the necessary length of wire.


2.A light bulb is connected to a 120.0 V wall socket. the current in the bulb depends on the time (t) according to the relation I = (0.707 A)sin[(314Hz)t]. (a) what is the frequency of the alternating current? (b) determine the resistance of the bulb's filament. (c) what is the aaverage power deliever to the light bulb?


Could someone please help me out
 
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P=V2/R will help you.

I=I0sin(ωt)
 

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