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An object is attached to coiled spring. The object is pulled down ( negative direction from the rest position) and then released. Write an equation for the distance of the object from its rest position after t seconds.Amplitude = 9 cm;Period = 3 seconds

User Dominican
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18 votes

We will investigate how to express a motion of a particle in one dimension using simple harmonics.

A simple harmonic function is trigonometric representation of motion of any body that oscillates about its mean position ( Xm ). An object is attached to a spring and pulled down. We will define the one dimensional coordinate axis in the vertical direction as (upward- positive) and (downward-negative):

The mean position of any object hanging down a spring is denoted by the length of the spring stretch under the weight of the object.

If we pull the object down in the ( negative direction ) the object will oscillate about its mean position ( Xm ) i.e up and down the mean position.

While oscillating the object will achive its maximum displacement about its mean position both above and below ( Xo ). This maximum displacement is called the amplitude of oscillation. The Amplitude of oscillation is given to us as follows:


\text{Amplitude ( X}_o)\text{ = 9 cm}

All oscillations are measured in terms of time period ( T ) which denotes the time taken to complete one cycle. The time started from when the object was released from ( -Xo ) the obect moved up due to the restoring force in spring and crosses its mean position then reach the maximum displacement ( +Xo ). Then the object reverses direction and moves down under gravity and crosses the mean position ( Xm ) an reach back to its initial start point ( -Xo ). This constitutes a complete cycle. The amount of time to complete one cycle of oscillation takes:


\text{Time Period ( T ) = 3 seconds}

The general simple harmonic function is represented by the followin trigonometric function. This function relates the displacement ( X ) of the object at any point in time ( t ) during the oscillating motion:


X(t)=X_o\cdot\cos \text{ ( }(2\pi)/(T)\cdot t)

We will plug in the respective paramters of a simple harmonic motion i.e ( Amplitue ) and ( Time Period ).


X(t\text{ ) = -9 cos ( }(2)/(3)\pi t\text{ ) }

An object is attached to coiled spring. The object is pulled down ( negative direction-example-1
User Casimiro
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