Hello Everyone,
As one might suspect from first glance, I assure you this isn't a homework problem. I am not in college but I found these problems to help me improve upon KCL and KVL.
My first problem, as depicted in the attachment, wants you to find the power in element A. According to Ohm's Law this is simple enough: P = VI so it should be 15W. However, the answer is actually -15W! How is this so? Wouldn't negative power be considered to be power absorbed by the element rather than dissipated? Also, you may notice that the current direction and voltage polarity are both positive compared to eachother. Does this make them negative? What if I reversed either the current direction or the voltage polarity, would that make it positive?
Thanks,
Austin
As one might suspect from first glance, I assure you this isn't a homework problem. I am not in college but I found these problems to help me improve upon KCL and KVL.
My first problem, as depicted in the attachment, wants you to find the power in element A. According to Ohm's Law this is simple enough: P = VI so it should be 15W. However, the answer is actually -15W! How is this so? Wouldn't negative power be considered to be power absorbed by the element rather than dissipated? Also, you may notice that the current direction and voltage polarity are both positive compared to eachother. Does this make them negative? What if I reversed either the current direction or the voltage polarity, would that make it positive?
Thanks,
Austin
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