The expression that models d, the horizontal distance in inches of the pendulum from the center as a function of time, t, in seconds is d=9cosine[(π/2)t] option second is correct.
It is defined as the number of waves that crosses a fixed point in one second, known as frequency. The unit of frequency is per second.
The pendulum takes 2 seconds to swing a horizontal distance of 18 inches from right to left.
For swing back from left to right, it takes again 2 seconds to cover a horizontal distance of 18 inches.
The total time to complete the one cycle = 4 seconds
Thus, the frequency is the reciprocal of the time
f = 1/4
The expression for the angular speed is:
w = 2πf
w = 2π(1/4)
w = π/2
The distance of the pendulum from the center A = half the horizontal
distance of 18 inches
A = 18/2
A = 9 inches
We know the cosine function for the pendulum is given by:
d = Acosine(wt)
d = 9cosine(πt/2) or
d = 9cosine[(π/2)t]
Thus, the expression that models d, the horizontal distance in inches of the pendulum from the center as a function of time, t, in seconds is d = 9cosine[(π/2)t]
Learn more about the frequency here:
brainly.com/question/27063800