Question
From the definition of linear SHM, derive an expression for the angular frequency of a body performing linear SHM.

Answer


When a body of mass $m$ performs linear SHM, the restoring force on it is always directed towards the mean position and its magnitude is directly proportional to the magnitude of the displacement of the body from the mean position. Thus, if $\vec{F}$ is the force acting on the body when its displacement from the mean position is $\vec{x}$,
$\vec{F}= m \vec{a}=- kx \vec{x}$
where the constant $k$, the force per unit displacement, is called the force constant.
Let $\frac{k}{m}=\omega^2$, a constant.
$\therefore$ Acceleration, $a=-\frac{k}{m}=-\omega^2 x$
$\therefore$ The angular frequency,
$\omega=\sqrt{\frac{k}{m}}=\sqrt{\left|\frac{a}{x}\right|}$
$=\sqrt{\text { acceleration per unit displacement }}$

Need a full question paper?

Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.

Start Generating Free

Similar questions

Two tuning forks when sounded together produce $5$ beats per second. A sonometer wire of length $0.24 m$ is in unison with one of the forks. When the length of wire is increased by $1\ cm$, it is in unison with the other fork. Find the frequencies of the tuning forks.
The photoelectric work function for a metal is \(4.2 eV\). If the stopping potential is \(3 V\), find the threshold wavelength and maximum kinetic energy of emitted electrons. (Velocity of light in air \(=3 \times 10^8 m / s\),) Planck's constant \(=6.63 \times 10^{-34} J - s\), Charge on electron \(=1.6 \times 10^{-19} C\) )
At what distance from the mean position is the kinetic energy of a particle performing S.H.M. of amplitude 8 cm, three times its potential energy?
Two wheels have the same mass. First wheel is in the form of a solid disc of radius $\mathrm{R}$ while the second is a disc with inner radius $r$ and outer radius $R$. Both are rotating with same angular velocity $\omega_0$ about transverse axes through their centres. If the first wheel comes to rest in time $t_1$ while the second comes to rest in time $t_2$, are $t_1$ and $t_2$ different? Why?
The velocity of the three molecules is $2 km s^{-1}, 4 km s^{-1}, 6 km s^{-1}.$
Find (i) mean square velocity (ii) root mean square velocity.
A long solenoid of length l, cross-sectional area A and having N1 turns (primary coil) has a small coil of N2 turns (secondary coil) wound about its centre. Determine the Mutual inductance (M) of the two coils.
Draw a diagram showing the linear velocity, angular velocity and radial acceleration of a particle performing circular motion with radius r.
Explain briefly the double-slit diffraction pattern.
A stone of mass $2 \mathrm{~kg}$ is whirled in a horizontal circle attached at the end of a $1.5 \mathrm{~m}$ long string. If the string makes an angle of $30^{\circ}$ with the vertical, compute its period.
The angular momentum of a body changes by $80 \mathrm{~kg} \cdot \mathrm{m}^2 / \mathrm{s}$ when its angular velocity changes from $20 \mathrm{rad} / \mathrm{s}$ to $40 \mathrm{rad} / \mathrm{s}$. Find the change in its kinetic energy of rotation.