A mass of 30 gm is attached with two springs having spring constants 100 N/m and 200 N/m and other ends of springs are attached to rigid walls as shown in the given figure. The angular frequency of oscillation is: (Ground is smooth)

                      

1.  $\frac{100}{2\mathrm{\pi }}$ rad/s 

2.  $\frac{100}{\mathrm{\pi }}$ rad/s

3.  100 rad/s

4.  200$\mathrm{\pi }$ rad/s

If a bob of the simple pendulum having negative charge q is made to oscillate in a uniform electric field acting vertically upward direction, then its time period:

1.  Increases

2.  Decreases

3.  No effect of the electric field

4.  Decreases or increases

A simple pendulum of length l and bob of mass m is executing S.H.M with amplitude A. The maximum tension in the string will be

1.  $\mathrm{mg}\left(\frac{\mathrm{l}}{\mathrm{l} + \mathrm{A}}\right)$

2.  $\mathrm{mg}\left(\frac{{\mathrm{l}}^2 + {\mathrm{A}}^2}{{\mathrm{l}}^2}\right)$

3.  $\mathrm{mg}\left(\frac{{\mathrm{l}}^2}{{\mathrm{l}}^2 + {\mathrm{A}}^2}\right)$

4.  $\mathrm{mg}\left(\frac{\mathrm{l} + \mathrm{A}}{\mathrm{l}}\right)$

Find the percentage change in time period if the length of a simple pendulum is increased by 3% 

1.  3%

2.  6%

3.  1.5%

4.  2.5%

A disc is oscillating about a horizontal axis passing through its rim and perpendicular to the plane of the disc. If the radius of the disc is R, then the frequency of oscillation is

1.  $2\mathrm{\pi }\sqrt{\frac{3g}{2R}}$

2.  $2\mathrm{\pi }\sqrt{\frac{2\mathrm{R}}{3\mathrm{g}}}$

3.  $\frac{1}{2\mathrm{\pi }}\sqrt{\frac{3\mathrm{R}}{2\mathrm{g}}}$

4.  $\frac{1}{2\mathrm{\pi }}\sqrt{\frac{2\mathrm{g}}{3\mathrm{R}}}$

The amplitude of a damped oscillator becomes one-third in 10 minutes and $\frac{1}{\mathrm{n}}$ times of the original value in 30 minutes. The value of n is:

1.  81

2.  3

3.  9

4.  27

A particle is executing SHM with time period T. The time taken by it to travel from mean position to $\frac{1}{\sqrt{2}}$ times its amplitude is equal to

1.  $\frac{\mathrm{T}}{6}$

2.  $\frac{\mathrm{T}}{12}$

3.  $\frac{\mathrm{T}}{8}$

4.  $\frac{\mathrm{T}}{4}$

A block of mass 2 kg is hanging with a massless spring and the spring is stretched by 40 cm. If the block is pulled down and released, then the period of oscillation is: (here, g = 10 $\mathrm{m}/{\mathrm{s}}^2$)

1.  $\frac{3}{5}\pi s$

2.  $\frac{5}{2}\pi s$

3.  $\frac{2}{5}\pi s$

4.  $\frac{5}{3}\pi s$

A spring is attached vertically to the ceiling of a lift and the lower end of spring is connected with a block of mass \(2~\text{kg}\). If the lift starts accelerating upwards with an acceleration \(2~\text{m/s}^2,\) then find the amplitude of SHM, while the spring constant is \(100~\text{N/m}\):
1. \(8~\text{cm}\)
2. \(1~\text{cm}\)
3. \(2~\text{cm}\)
4. \(4~\text{cm}\)

The motion of the particle is started at t = 0 and the equation of motion is given by $x = 8 \sin \left(100t + \frac{\mathrm{\pi }}{6}\right)$, where x is in cm and t is in seconds. When will the particle come to rest for the first time?

1.  $\frac{\mathrm{\pi }}{300} \mathrm{s}$

2.  $\frac{\mathrm{\pi }}{200} \mathrm{s}$

3.  $\frac{\mathrm{\pi }}{100} \mathrm{s}$

4.  $\frac{\mathrm{\pi }}{400} \mathrm{s}$