AP Physics E&M 2010 FRQ

<p>Hey guys, quick question:</p>

<p>On 2f. I was wondering why I wouldn't get the same answers if I used P=IV as opposed to P=I^2*R. The current through the circuit is 0.5 A, the voltage is 30 V, and the resistance is 40 ohms. </p>

<p><a href="http://apcentral.collegeboard.com/apc/public/repository/ap10_frq_physics_c_e_m.pdf%5B/url%5D"&gt;http://apcentral.collegeboard.com/apc/public/repository/ap10_frq_physics_c_e_m.pdf&lt;/a>
<a href="http://apcentral.collegeboard.com/apc/public/repository/ap10_physics_c_em_scoring_guidelines.pdf%5B/url%5D"&gt;http://apcentral.collegeboard.com/apc/public/repository/ap10_physics_c_em_scoring_guidelines.pdf&lt;/a&gt;&lt;/p>

<p>Can anyone help?</p>