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An object's motion is described by the equation d = 4 sin(pi t ) . The displacement, d , is measured in meters. The time, t , is measured in seconds. Answer the following questions:

AWhat is the object's position at t = 0 ?
BWhat is the object's maximum displacement from its resting position?
CHow much time is required for one oscillation?
DWhat is the frequency?

Verified Answer :

The equation of the motion is
d = 4 sin (π t)

a) When t = 0
d = 4 sin 0
d = 0

b) We take the derivative
4π cos πt = 0
t = 1/2
d = 4 sin π/2 = 4 meters

c) 1 second is required

d) The frequency is 1Hz

Answer:

Step-by-step explanation:

The given equation is:

\(d=4sin({\pi}t)\), where d is the displacement.             (1)

(A) The position of the object at t=0 is:

\(d=4sin({\pi}(0))\)

⇒\(d=4sin(0)\)

⇒\(d=0\)

The object will be at rest at t=0.

(B) In order to find the maximum displacement from the resting position, we will differentiate the given displacement.

Thus,  Differentiating with respect to t, we have

\(d'=4cos({\pi}t)({\pi})\)

⇒\(d'=4{\pi}cos({\pi}t)\)

Now, d'=0

⇒\(4{\pi}cos({\pi}t)=0\)

⇒\(cos{\pi}t=0\)

⇒\({\pi}t=\frac{{\pi}}{2}\)

⇒\(t=\frac{1}{2}\)

Substitute the value of t in equation (1), we get

⇒\(d=4sin({\pi}(\frac{1}{2}))\)

⇒\(d=4(1)\)

⇒\(d=4m\)

Thus, the maximum displacement from its resting position will be 4m.

(C) Time required for one oscillation is equal to the period which is equal to=\(\frac{2\pi}{|b|}=\frac{2\pi}{\pi}=2\)

thus,  time  required for one oscillation will be 2 seconds.

(D) Frequency is nothing but the reciprocal of period that is \(\frac{|b|}{2\pi}=\frac{\pi}{2\pi}=\frac{1}{2}\)

Thus, the frequency will be equal to \(\frac{1}{2}\).