1. The problem The answer is A. 2. Relevant equations x = Acoswt y = Asinwt 3. The attempt at a solution C is not correct because the x & y positions are in terms of sin & cos, so the acceleration can't be constant. D is not correct because x & y are oscillating in value. E is not correct because y is changing with time Therefore it's either A or B, which makes sense since x & y are oscillating, they have to form some sort of circle. I'm stuck between A & B. How do you know the particle is moving with constant speed? B/c the acceleration is definitely not 0. In fact, how do you know these 2 functions describe a circle?