Combining Resistors for 5W Dissipation in 10 Ohms

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To achieve a 10-ohm resistor capable of dissipating at least 5 watts using 10 resistors rated at 1 watt each, a combination of series and parallel configurations is necessary. Initially, confusion arose regarding how multiple resistors could maintain the desired resistance while increasing power dissipation. The solution involves connecting resistors in parallel to lower the overall resistance and then combining those pairs in series to meet the power requirement. Ultimately, the minimum number of resistors needed is five, which allows for a total power dissipation of 5 watts. The discussion highlights the importance of understanding both resistance and power calculations in resistor configurations.
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Homework Statement


You are given a number of 10 resistors, each capable of dissipating only 1.0 W without being
destroyed. What is the minimum number of such resistors that you need to combine in series or
in parallel to make a 10 resistor that is capable of dissipating at least 5.0 W?


Homework Equations





The Attempt at a Solution


I don't understand the problem. I can't see how the final resistance can be 10 if there is more than one resistor. But at the same time I don't get how the power can be 5 with just one..

Help please, we haven't really seen this in class.
 
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Start with 4 resistors. What is the resultant resistance of two parallel resistors each of resistance R? And what happens if you connect two such pairs in series?

ehild
 
OKay, so i got the resistance (I was doing wrong calculations) but I don;t get the power to be 5 but 4 W...
 
Try connecting more resistors. You need 5 at least.ehild
 
I got it now ! thank you :)
 

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