下面给大家分享的是一道SAT2的物理真题及其解法。

　　The set of lettered choices below refers to multiple questions. Select the one lettered choice that best answers each question. A choice may be used once, more than once, or not at all in each set.

　　Which graph represents the total heat developed from time

　　by a resistor carrying a steady current?

　　Answer Choices

　　(A)

　　(B)

　　(C)

　　(D)

　　(E)

　　The correct answer is A

　　Explanation

　　Difficulty: Easy

　　The correct answer is a steadily increasing amount. The rate of heat dissipation by a resistor is equal to the power it expends. The power is related to the current and the resistance by the equation , so if the current is constant the power is constant. The total heat developed is then the power multiplied by the total time .

　　The graph is thus a steadily increasing function of time.

　　SAT2物理真题是备考SAT2物理考试很好的参考材料，希望以上的分享对大家的备考有所帮助。