MCQ
Which of the following statement is not correct
  • A
    Photographic plates are sensitive to infrared rays
  • B
    Photographic plates are sensitive to ultraviolet rays
  • C
    Infra-red rays are invisible but can cast shadows like visible light
  • Infrared photons have more energy than photons of visible light

Answer

Correct option: D.
Infrared photons have more energy than photons of visible light
d
(d) $E \propto \frac{1}{\lambda };$ also ${\lambda _{{\rm{infrared}}}} > {\lambda _{{\rm{visible}}}}$ so ${E_{{\rm{infrared}}}} < {E_{{\rm{visible}}}}$

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 solid sphere of mass $1\ kg$ rolls on a table with linear speed $1\ m/s$. Its total kinetic energy is .......... $J$
In electromagnetic induction, the induced $e.m.f$. in a coil is independent of
Two forces are such that the sum of their magnitudes is $18 \,N$ and their resultant is perpendicular to the smaller force and magnitude of resultant is $12\, N$. Then the magnitudes of the forces are
Three resistances of one ohm each are connected in parallel. Such connection is again connected with $\frac{2}{3}\,\Omega $ resistor in series. The resultant resistance will be  ........... $\Omega$
A capacitor is connected to a $10\,V$ battery. The charge on the plates is $10\,\mu C$ when medium between plates is air. The charge on the plates become $100\,\mu C$ when space between plates is filled with oil. The dielectric constant of oil is
When a particle is restricted to move along $x$-axis between $x=0$ and $x=a$, where $a$ is of nanometer dimension, its energy can take only certain specific values. The allowed energies of the particle moving in such a restricted region, correspond to the formation of standing waves with nodes at its ends $x=0$ and $x=a$. The wavelength of this standing wave is related to the linear momentum $p$ of the particle according to the de Broglie relation. The energy of the particle of mass $m$ is related to its linear momentum as $E=\frac{p^2}{2 m}$. Thus, the energy of the particle can be denoted by a quantum number ' $n$ ' taking values $1,2,3, \ldots \quad(n=1$, called the ground state) corresponding to the number of loops in the standing wave.

Use the model described above to answer the following three questions for a particle moving in the line $x=0$ to $x=a$. Take $h=6.6 \times 10^{-34} \mathrm{~J} \mathrm{~s}$ and $e=1.6 \times 10^{-19} \mathrm{C}$.

$1.$ The allowed energy for the particle for a particular value of $n$ is proportional to

$(A)$ $a^{-2}$ $(B)$ $a^{-3 / 2}$ $(C)$ $a^{-1}$ $(D)$ $a^2$

$2.$ If the mass of the particle is $m=1.0 \times 10^{-30} \mathrm{~kg}$ and $a=6.6 \mathrm{~nm}$, the energy of the particle in its ground state is closest to

$(A)$ $0.8 \ \mathrm{meV}$ $(B)$ $8 \ \mathrm{meV}$ $(C)$ $80 \ \mathrm{meV}$ $(D)$ $800 \ \mathrm{meV}$

$3.$ The speed of the particle, that can take discrete values, is proportional to

$(A)$ $n^{-3 / 2}$ $(B)$ $n^{-1}$ $(C)$ $n^{1 / 2}$ $(D)$ $n$

Give the answer question $1, 2$ and $3.$

If the mass of neutron is $1.7 \times 10^{-27} \;kg$, then the de-Broglie wavelength of neutron of energy $3\; eV$ is

$\left(h=6.6 \times 10^{34} \;J \cdot sec\right)$,

The diagram of a logic circuit is given below. The output $F$ of the circuit is represented by
An electron of mass $m$ and charge $e$ is accelerated from rest through a potential difference $V$ in vacuum. The final speed of the electron will be
Three perfect gases at absolute temperatures $T_1 , T_2$ and $T_3$ are mixed. The masses of molecules are $m_1 , m_2$ and $m_3$ and the number of molecules are $n_1, n_2$ and $n_3$ respectively. Assuming no loss of energy, the final temperature of the mixture is