500 ohm resister fed from 120 VP-Pac source

[stevielee]

Homework Statement

a 500 ohm resister is fed by 120 Volt P-Peak ac source;How much heat does the resister dissipate if the signal is a sine wave or a square wave?

Homework Equations

The Attempt at a Solution

 

[ideasrule]

What's the equation for power dissipated by a resistor?

 

[stevielee]

I don't know I just started this course and what happened is they offered an ac circuts short course with no prerequisites and actually all but three of us have been in the class under DC circuts for three months now, we are so behind and we really want to understand and it's a ***** when your so uninformed about basic formulas and such, I refuse to give up so, no I don't know what that equation is all the quest wants is how much neat is lost when 120 volts peak is put across a circute with a 500 ohm resister in it and how much is lost in a sine wave or a square wave?

 

[gneill]

If it were a DC circuit, what would be the power dissipated given that the potential difference across the resistor is V?

 

[rwisz]

To calculate the heat dissipated by the resistor, we can use the formula P = I^2*R, where P is power (in watts), I is current (in amperes), and R is resistance (in ohms).

For a sine wave, the peak current (I) can be calculated using the formula I = V/R, where V is the peak voltage (in volts). In this case, the peak voltage is 120 volts, so the peak current would be 120/500 = 0.24 amperes.

To find the power, we need to square the current and multiply by the resistance. So, P = (0.24)^2 * 500 = 28.8 watts. This is the amount of heat that the resistor would dissipate when connected to a sine wave 120 volt P-Pac source.

For a square wave, the peak current would be the same as for a sine wave, 0.24 amperes. However, the power would be different because the current is constant throughout the square wave. So, P = (0.24)^2 * 500 = 28.8 watts.

Both the sine wave and square wave would dissipate the same amount of heat, 28.8 watts, in the 500 ohm resistor. This is because the power dissipated by a resistor is dependent on the current and resistance, not the type of waveform.