Instructions: In this task you will be given a text passage from a trivia quiz. You should choose the category this question belongs to from these categories: History, Science, Social Science, Fine Arts, Literature. You can only choose one category, so if in doubt, please choose the closest match.
Input: For an RLC circuit, the frequency associated with this effect is where impedance is at a minimum. Substances can be analyzed through a technique that uses the nuclear magnetic form of this effect. That technique's commonly used medical variant is called MRI. This effect causes the amplitude of a system to hit a maximum. For a vibrating string, the frequencies of this are multiples of the fundamental. For 10 points, name this effect where the frequency of the input force equals the natural frequency of the system.
Output:
Science