CollegeBoard SAT Physics Study Guide PT1 Q28

CollegeBoard's Book

28) This problem asks us to find the time it takes for the cork to complete one oscillation. Since we are dealing with waves we can use this equation.

Where v is velocity, f is frequency, and lamda is wavelength

We need to find the time it takes the cork to complete one oscillation, also known as the period. Well, since frequency and period are reciprocals of each other, we can rewrite this equation.

Where f is frequency, T is period, v is velocity, and lamda is wavelength

The question tells us that the speed is 2.0 meters per second, but we still need the wavelength to figure out the period of the oscillation. A wavelength is the distance traveled by the wave in one cycle. Our cycle is one crest(peak) and one trough(valley). Let's take a look at the given graph to find the wavelength.

Now that we know our wavelength is 5 meters, we can plug in our values to our equation and solve for the period(T).

Where v is velocity, lamda is wavelength, and T is period

Answer: D