2022TrialShort answer

Q14 (b) (ii)

2 marks

Question

A particle is moving so that $x=2\sin3t-2\sqrt3\cos3t$ . Find the initial position and velocity of the particle.

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Solution

(ii) Initial position:

4\sin\left(-\frac\pi3\right)=-2\sqrt3\text{ m}

$-2\sqrt3$ m left of $O$ .

Initial velocity:

v=12\cos\left(3t-\frac\pi3\right)

$t=0$ :

v=12\cos\left(-\frac\pi3\right)=6\text{ m/s}.

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Syllabus alignment

Mechanics

Simple harmonic motionDerive and interpret displacement, velocity and acceleration models for simple harmonic motion.

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