Tag: oscillation and waves

Quizzes (19) Questions (170)

Questions Related to oscillation and waves

Multiple choice force in shm oscillations oscillation and waves physics

A particle is in S.H.M of amplitude $ 2$ cm. At extreme position the force is $4$N. At the point mid-way between mean and extreme position, the force is :

  1. $1$ N
  2. $2$N
  3. $3$N
  4. $4$N
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Amplitude = 2 cm
Force = 4N
$F = mw^{2}A=4$
$F _{1} = mw^{2}x$

Since $F$ is directly proportional to $x$ so , at midpoint the force when the amplitude is $2 \ cm$ will be $2N$

Multiple choice force in shm oscillations oscillation and waves physics

A 1 kg mass executes SHM with an amplitude 10 cm, it takes $2\pi$ seconds to go from one end to the other end. The magnitude of the force acting on it at any end is :

  1. 0.1 N

  2. 0.2 N

  3. 0.5 N

  4. 0.05 N
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

As $  w  = \cfrac{2\pi}{T} = 1 \ rad/sec $ ;    Amplitude  $A  = 0.1 m$
magnitude of  force $ = m \times w^{2}.A$
                                  $=  0.1 N$

Multiple choice force in shm oscillations oscillation and waves physics

An elastic ball of density $d$ is released and it falls through a height $h$ before striking the surface of liquid of density $\rho(d < \rho)$. The motion of ball is:

  1. Periodic

  2. S.H.M.

  3. Circular

  4. Parabolic
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

When the ball hits the liquid, it experiences a buoyant force greater than its weight (since d < rho), causing it to decelerate and eventually rise. It will oscillate between the surface and the depth, making the motion periodic, but it is not SHM because the forces are not linear with displacement.

Multiple choice force in shm oscillations oscillation and waves physics

A body of mass 1/4 kg is in S.H.M and its displacement is given by the relation $y= 0.05 sin(20t+\dfrac{\pi }{2})$ m. If $t$ is in seconds, the maximum force acting on the particle is:

  1. $5$ N
  2. $2.5$ N
  3. $10$ N
  4. $0.25$ N
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

$F= m\omega^{2}A$
$\omega = 20   rad / sec$
$A =   0.05   m$
Thus
$F= \dfrac{1}{4}\times 20\times 20\times \dfrac{1}{20}$
$=5 N $

Multiple choice energy in wave motion oscillation and waves waves physics

If the energy density and velocity of a wave are $u$ and $c$ respectively then the energy propagating per second per unit area will be

  1. $u/c$
  2. $c^2u$
  3. $uc$
  4. $c/u$
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

If the energy density and velocity of a wave are $u$ and $c$ respectively then the energy propagating per second per unit area will be $uc.$

Multiple choice energy in wave motion oscillation and waves waves physics

The kinetic energy per unit length for a wave on a string is the positional coordinate

  1. True

  2. False
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

The kinetic energy for a particle is given by $(\mu \Delta x/ 2) (\dfrac{dy}{dt})^2$

Thus, it depends only on the time variable and not on the position variable

Multiple choice energy in wave motion oscillation and waves waves physics

A travelling wave has an equation of the form $A(x,t)=f(x+vt)$. The relation connecting positional derivative with time derivative of the function is:

  1. $\dfrac{dA}{dt}=\pm v^2 \dfrac {dA}{dx}$
  2. $\dfrac{dA}{dt}=\pm v \dfrac {dA}{dx}$
  3. $\dfrac{dA}{dt}=\pm \sqrt(v) \dfrac {dA}{dx}$
  4. $\dfrac{dA}{dt}=(2 \pi v/\lambda) \dfrac {dA}{dx}$
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Positional derivative and time derivative of a function f is $\dfrac{dA}{dt}=\pm v \dfrac {dA}{dx}$

The correct option is (b)

Multiple choice energy in wave motion oscillation and waves waves physics

Kinetic energy per unit length for a particle in a standing wave is zero at:

  1. nodes

  2. antinodes

  3. mid-way between a node and an antinode

  4. None of the above
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Particle at antinodes is momentarily at rest and hence has zero kinetic energy. Its speed comes down to zero at this point and all energy is stored in the form of potential energy.

Multiple choice energy in wave motion oscillation and waves waves physics

The total energy per unit length for a travelling wave in a string of mass density $\mu$ , whose wave function is $A(x,t) = f(x \pm vt)$ is given by: 

  1. $E _tot = \sqrt(\mu/2) (\dfrac{dA}{dt})^2$
  2. $E _tot = (\mu/2) (\dfrac{dA}{dt})^2$
  3. $E _tot = (\mu/2)^2 (\dfrac{dA}{dt})^2$
  4. $E _tot = (2\mu) (\dfrac{dA}{dt})^2$
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

For a travelling wave y = f(x - vt), the energy density is related to the square of the partial derivative of the wave function with respect to time, specifically (mu/2) * (dy/dt)^2.