Question

A mass on a spring is set oscillating by first compressing the spring 3cm in the negative direction, then releasing the mass from rest. The period of oscillation is 1s. Which equation(s) best describes the position as a function of time? Select one or more:

A. x = 3cm cos(2π t +π)

B. x = -3cm cos(2π t + 0 )

C. x = 3cm cos(2π t + π/2 )

D. x = 3cm cos(2π t - π/2 )

Answer 1

The general expression for the oscillatory motion is

where A is the maxinmum amplitude, is the angular frequency and is phase constant

Amplitude of the mass is 3cm, angular frequency where T is time period, T=1s

Mass has maximum displacement in the negative x-direction, so φ = π.

The final expression for the oscillatory motion is

The Answer is Option A