Which of the following relationships between the acceleration $a$ and the displacement $x$ of a particle involve simple harmonic motion?
(c) $a = –10x$

Answer the following questions :
(b) The motion of a simple pendulum is approximately simple harmonic for small angle oscillations. For larger angles of oscillation, a more involved analysis shows that $T$ is greater than $2\pi \sqrt{\frac{l}{g}}$. Think of a qualitative argument to appreciate this result.

Which of the following examples represent (nearly) simple harmonic motion and which represent periodic but not simple harmonic motion?
(d) general vibrations of a polyatomic molecule about its equilibrium position.

You are riding in an automobile of mass 3000 kg. Assuming that you are examining the oscillation characteristics of its suspension system. The suspension sags 15 cm when the entire automobile is placed on it. Also, the amplitude of oscillation decreases by 50% during one complete oscillation. Estimate the values of (a) the spring constant $k$ and

Answer the following questions :
(a) Time period of a particle in SHM depends on the force constant $k$ and mass $m$ of the particle: $T = 2\pi \sqrt{\frac{m}{k}}$. A simple pendulum executes SHM approximately. Why then is the time period of a pendulum independent of the mass of the pendulum?

Which of the following examples represent periodic motion?
(c) A hydrogen molecule rotating about its centre of mass.

Which of the following examples represent periodic motion?
(b) A freely suspended bar magnet displaced from its N-S direction and released.

Answer the following questions :
(d) What is the frequency of oscillation of a simple pendulum mounted in a cabin that is freely falling under gravity ?

The acceleration due to gravity on the surface of moon is $1.7 m s^{-2}$. What is the time period of a simple pendulum on the surface of moon if its time period on the surface of earth is 3.5 s ? ($g$ on the surface of earth is $9.8 m s^{-2}$)

Which of the following relationships between the acceleration $a$ and the displacement $x$ of a particle involve simple harmonic motion?
(a) $a = 0.7x$

Which of the following examples represent (nearly) simple harmonic motion and which represent periodic but not simple harmonic motion?
(b) motion of an oscillating mercury column in a U-tube.

Plot the corresponding reference circle for each of the following simple harmonic motions. Indicate the initial ($t =0$) position of the particle, the radius of the circle, and the angular speed of the rotating particle. For simplicity, the sense of rotation may be fixed to be anticlockwise in every case: ($x$ is in cm and $t$ is in s).
(a) $x = –2 sin (3t + \pi/3)$

The piston in the cylinder head of a locomotive has a stroke (twice the amplitude) of 1.0 m. If the piston moves with simple harmonic motion with an angular frequency of 200 rad/min, what is its maximum speed ?

Which of the following functions of time represent (a) simple harmonic, (b) periodic but not simple harmonic, and (c) non-periodic motion? Give period for each case of periodic motion ($\omega$ is any positive constant):
(c) $3 cos (\frac{\pi}{4} – 2\omega t)$

Figures 14.25 correspond to two circular motions. The radius of the circle, the period of revolution, the initial position, and the sense of revolution (i.e. clockwise or anti-clockwise) are indicated on each figure. Obtain the corresponding simple harmonic motions of the x-projection of the radius vector of the revolving particle P, in each case.

Which of the following functions of time represent (a) simple harmonic, (b) periodic but not simple harmonic, and (c) non-periodic motion? Give period for each case of periodic motion ($\omega$ is any positive constant):
(d) $cos \omega t + cos 3\omega t + cos 5\omega t$

A particle is in linear simple harmonic motion between two points, A and B, 10 cm apart. Take the direction from A to B as the positive direction and give the signs of velocity, acceleration and force on the particle when it is
(b) at the end B,

Which of the following functions of time represent (a) simple harmonic, (b) periodic but not simple harmonic, and (c) non-periodic motion? Give period for each case of periodic motion ($\omega$ is any positive constant):
(a) $sin \omega t – cos \omega t$

An air chamber of volume $V$ has a neck area of cross section $a$ into which a ball of mass $m$ just fits and can move up and down without any friction (Fig.14.27). Show that when the ball is pressed down a little and released , it executes SHM. Obtain an expression for the time period of oscillations assuming pressure-volume variations of air to be isothermal [see Fig. 14.27].

A particle is in linear simple harmonic motion between two points, A and B, 10 cm apart. Take the direction from A to B as the positive direction and give the signs of velocity, acceleration and force on the particle when it is
(a) at the end A,