Question 281: Oscillations

Question

In S.H.M. the displacement of a particle at an instant is $Y=A \cos 30^{\circ}$, where $A=40 \mathrm{~cm}$ and kinetic energy is 200 J . If force constant is $1 	imes 10^{	imes} \mathrm{N} / \mathrm{m}$, then x will be $\left(\cos 30^{\circ}=\sqrt{3} / 2ight)$

Accepted Answer

$$\begin{aligned}
& Y=A \cos 30^{\circ}=40 	imes \frac{\sqrt{3}}{2}=20 \sqrt{3} \mathrm{~cm} \
& 	ext { K.E. }=\frac{1}{2} k\left(A^2-Y^2ight) \
& 200=\frac{1}{2} k\left(\frac{1600}{10^4}-\frac{1200}{10^4}ight)
\end{aligned}$$
$$\begin{aligned}
& 200=\frac{1}{2} k\left(\frac{400}{10^4}ight) \
& k=10000=1 	imes 10^4 \
& 	herefore \quad x=4
\end{aligned}$$

Answer

4

Answer

3

Answer

2

Answer

1

Oscillations

In S.H.M. the displacement of a particle at an instant is Y=A \cos 30^{\circ}, where A=40 \mathrm{~cm} and kinetic energy is 200 J . If force constant is 1 \times 10^{\times} \mathrm{N} / \mathrm{m}, then x will be \left(\cos 30^{\circ}=\sqrt{3} / 2\right)

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