Electricity - Resistance problem

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SUMMARY

The discussion centers on calculating the resistance of a 240 W television operating for 4.0 hours daily. The user has identified relevant equations, including P = I^2 x R and P = V^2/R, but struggles to determine the next steps due to insufficient values for current or voltage. The total energy consumed is calculated as 3,456,000 J, but the user seeks guidance on how to derive resistance from the given power and time.

PREREQUISITES
  • Understanding of electrical power equations, specifically P = I x V and P = V^2/R.
  • Knowledge of the relationship between current (I), voltage (V), and resistance (R).
  • Familiarity with energy calculations in joules (E = P x ∆t).
  • Basic concepts of electrical systems in residential settings, particularly in Canada.
NEXT STEPS
  • Learn how to calculate current using P = V x I.
  • Study the characteristics of residential voltage supply in Canada (typically 120V).
  • Explore the application of Ohm's Law (V = I x R) in practical scenarios.
  • Investigate the conversion of power consumption into resistance using P = V^2/R.
USEFUL FOR

Students studying electrical engineering, physics enthusiasts, and anyone needing to solve electrical resistance problems in practical applications.

gvhunting
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Homework Statement



A 240 W television operates for 4.0 h a day in a typical Canadian home.
Calculate the resistance of the television.

Homework Equations



1) I = Q/∆ t 2) E = QxV 3) P = (Q x V)/ ∆t 4) P = I^2 x R
5) P = V^2/R 6) P = I x V 7) V = W/Q 8) V = E/Q
9) Q = I x ∆t 10) R = V/I


The Attempt at a Solution



Given:

P = 240 W
∆t = 4 h = 14 400 s
R = ?

E = P x ∆t
= 240 W x 14 400 s
= 3 456 000 J

I have done many practice problems but none such as this. I do not know where to go from here. There are many equations and I understand the most logical step next would be to either find the current or voltage and then using that value and Power to find the resistance. Or I can also find the value of Q and then using that and Power find either the current or voltage but not many values are given to do that.

Please help, I have been at this question for quite a while now, going around in circles.
 
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gvhunting said:

Homework Statement



A 240 W television operates for 4.0 h a day in a typical Canadian home.
Calculate the resistance of the television.

Homework Equations



1) I = Q/∆ t 2) E = QxV 3) P = (Q x V)/ ∆t 4) P = I^2 x R
5) P = V^2/R 6) P = I x V 7) V = W/Q 8) V = E/Q
9) Q = I x ∆t 10) R = V/I


The Attempt at a Solution



Given:

P = 240 W
∆t = 4 h = 14 400 s
R = ?

E = P x ∆t
= 240 W x 14 400 s
= 3 456 000 J

I have done many practice problems but none such as this. I do not know where to go from here. There are many equations and I understand the most logical step next would be to either find the current or voltage and then using that value and Power to find the resistance. Or I can also find the value of Q and then using that and Power find either the current or voltage but not many values are given to do that.

Please help, I have been at this question for quite a while now, going around in circles.
Hi gvhunting, Welcome to Physics Forums.

How is power related to voltage and current? How about resistance? What are the common characteristics of the electricity supplied to homes in Canada?
 

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