Topic 9 IB Physics

Which of the following is the correct expression for the displacement x?

• $-x_0\cdot\cos\ \frac{2\pi}{T}t$

• $x_0\cdot\cos\ \frac{2\pi}{T}t$

• $-x_0\cdot\sin\ \frac{2\pi}{T}t$

• $x_0\cdot\sin\ \frac{2\pi}{T}t$

A mass on the end of a spring is released from rest from an initial displacement A. Its oscillations have total energy E.

Later, the same mass is extended and released from a displacement of 2A. Which of the following gives the correct new time period and new total energy?

• Time period T; New energy 4E

• Time period T; New energy 2E

• Time period $\sqrt{2}T$ ; New energy 4E
  

• Time period $\sqrt{2}T$ ; New energy 2E
  

The period of a particle undergoing SHM is T. The ratio:  $\frac{acceleration\ of\ the\ particle}{displacement\ of\ the\ particle}$  is proportional to....

•  $T^{-2}$  

•  $T^{-1}$  

•  $T$  

•  $T^2$  

A small point mass m is placed at the same distance from two identical fixed spherical masses far from any other masses. The point mass is released from rest. The point mass will....

• move upwards.

• stay where it is.

• move towards P and stop there.

• oscillate about point P.

An object undergoes simple harmonic motion (SHM). The total energy of the object is proportional to....

• the amplitude of the oscillations.

• the time period of the oscillations.

• the frequency of the oscillations.

• the mass of the object.

A beam of coherent light is incident on a single slit of width b. After passing through the slit, the light is incident on a screen at a distance D from the slit.

Which of the following changes, carried out separately, in respect of b and D will result in an increase in width of the first diffraction maximum formed on the screen?

• b decrease and D increase.

• b increase and D increase.

• b decrease and D decrease.

• b increase and D decrease.

A parallel beam of monochromatic light of wavelength λ passes through a slit of width b. After passing through the slit the light is incident on a distant screen. The angular width of the central maximum is

• $2\ \frac{\lambda}{b}$ radians

• $\frac{\lambda}{b}$ radians

• $2\ \frac{\lambda}{b}$ degrees

• $\frac{\lambda}{b}$ degrees
  

A single-slit diffraction experiment is performed using light of different colours. The width of the central peak in the diffraction pattern is measured for each colour. What is the order of the colours that corresponds to increasing widths of the central peak?

• red, green, blue

• red, blue, green

• blue, green, red

• green, blue, red

In a double-slit interference experiment, the following intensity pattern is observed for light of wavelength λ. The distance between the slits is d. What can be deduced about the value of the ratio $\frac{\lambda}{d}$and the effect of single-slit diffraction in this experiment?

•  $\frac{\lambda}{d}$  is 100; the diffraction is non-negligible
  

•  $\frac{\lambda}{d}$  is 0.01; the diffraction is non-negligible
  

•  $\frac{\lambda}{d}$  is 100; the diffraction is negligible
  

•  $\frac{\lambda}{d}$  is 0.01; the diffraction is negligible
  

A transparent liquid forms a parallel-sided thin film in air.

Reflections from the top and bottom surfaces of the film result in three rays J, K and L. Which of the rays has undergone a phase change of π rad?

• J only

• J and L only

• J and K only

• J, K and L