1. The problem statement, all variables and given/known data A body performaning simple harmonic motion has a displacement x given by the equation x= 30 sin 50t, where t is the time in seconds. what is the frequency of the oscillation? Answers are: A. 0.020Hz B. 0.13Hz C. 8.0Hz D. 30Hz E. 50Hz (correct answer is B according to the mark scheme) 2. Relevant equations ω = 2πf x = Amplitude cos (2πf t) x = Amplitude sin (2πf t) x = Amplitude cos (ω t) x = Amplitude cos (ω t) 3. The attempt at a solution f = 50/2π = 7.9577Ηz according to the standard SHM formulas, which means the answer is C not B? what has gone wrong?