Number of Resistors needed for a maximum power

AI Thread Summary
To determine the number of 70-ohm resistors that can be connected in a series circuit with a maximum power loss of 1800W and a supply voltage of 127V, the power formula P = V² / (x * R) is used. The calculation reveals that only one resistor can be connected, as the derived value for x is approximately 1.28. There was initial confusion regarding the resistor value, with a typo indicating 7 ohms instead of 70 ohms, but it was clarified that the correct value is indeed 70 ohms. The conclusion remains that only one resistor can be utilized in this configuration. This analysis confirms the relationship between resistance, voltage, and power in series circuits.
chawki
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Homework Statement


How many resistors, R = 70 ohms can be connected in a series circuit when the maximum power loss of the circuit is 1800W. and the voltages supply is 127V


Homework Equations


Number of resistors!


The Attempt at a Solution


P = V2 / x*R
x*7=1272/1800
x=1.28

so only one resistor can be connected.
 
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chawki said:

Homework Statement


How many resistors, R = 70 ohms can be connected in a series circuit when the maximum power loss of the circuit is 1800W. and the voltages supply is 127V


Homework Equations


Number of resistors!


The Attempt at a Solution


P = V2 / x*R
x*7=1272/1800
x=1.28

so only one resistor can be connected.

Are the resistors 7 Ω or 70 Ω? Your problem statement says 70, but you've used 7 in your calculation.
 
no it's 7 Ohms. sorry for the typing mistake.
 
chawki said:

Homework Statement


How many resistors, R = 70 ohms can be connected in a series circuit when the maximum power loss of the circuit is 1800W. and the voltages supply is 127V


Homework Equations


Number of resistors!


The Attempt at a Solution


P = V2 / x*R
x*7=1272/1800
x=1.28

so only one resistor can be connected.
If R=7Ω , then this is correct !
 

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