MCQ
A particle performs $S.H.M.$ of amplitude $A$ with angular frequency $\omega$  along a straight line. Whenit is at a distance  $\frac{{\sqrt 3 }}{2}$ $A$  from mean position, its kinetic energy gets increased by an amount $\frac{1}{2}m{\omega ^2}{A^2}$  due to an impulsive force. Then its new amplitude becomes
  • A
    $\frac{{\sqrt 5 }}{2}A$
  • B
    $\frac{{\sqrt 3 }}{2}A$
  • $\sqrt 2$ $A$
  • D
    $\sqrt 5$ $A$

Answer

Correct option: C.
$\sqrt 2$ $A$
c
Due to impulse force, the total energy of the particle becomes

$\frac{1}{2} m \omega^{2} A^{2}+\frac{1}{2} m \omega^{2} A^{2}=m \omega^{2} A^{2}$

Let $A^{\prime}$ be the new amplitude. (apply energy conservation law)

$\frac{1}{2} m_{\omega}^{2}\left(A^{\prime}\right)=m_{\omega}^{2} A^{2}$

${A}^{\prime}=\sqrt{2} A$

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

A $72 \; \Omega$ galvanometer is shunted by a resistance of $8 \; \Omega$. The percentage of the total current which passes through the galvanometer is $.....$
Frequency of a sonometer wire is $n.$ Now its tension is increased $4$ times and its length is doubled then new frequency will be
Which of the following expressions corresponds to simple harmonic motion along a straight line, where $x$ is the displacement and $a, b, c$ are positive constants?
A liquid does not wet the sides of a solid, if the angle of contact is
A wheel of radius $R$ with an axle of radius $R/2$ is shown in the figure and is free to rotate about a frictionless axis through its centre and perpendicular to the page. Three forces $(F, F, 2F)$ are exerted tangentially to the respective rims as shown in the figure. The magnitude of the net torque acting on the system is nearly 
In short wave communication waves of which of the following frequencies will be reflected back by the ionospheric layer, having electron density $10^{11}$ per $m^{3}$.......$MHz$
A point electric dipole placed at the origin has a potential given by $V(r, \theta)=\frac{p \cos \theta}{4 \pi \varepsilon_0 r^2}$, where $\theta$ is the angle made by the position vector with the direction of the dipole. Then,
In a Young’s double slit experiment, the path difference, at a certain point on the screen, between two interfering waves is $1/8^{th}$ of wavelength. The ratio of the intensity at this point to that at the centre of a bright fringe is close to
If $\lambda_1$ and $\lambda_2$ denote the wavelengths of de Broglie waves for  electrons in the first and second Bohr orbits in a hydrogen atom, then $\lambda_1/\lambda_2$ is equal to 
A wheel with ten metallic spokes each $0.50\,m$ long is rotated with a speed of $120\, rev/min$ in a plane normal to the earth’ s magnetic field at the place. If the magnitude of the field is $0.40\,G$, the induced $emf$ between the axle and the rim of the wheel is equal to