Question 2 :
Total internal reflection of light is possible when light enters from[CPMT 1973; MP PMT 1994]
Question 5 :
A Youngs double slit experiment uses a monochromatic source. The shape of the interference fringes formed on a screen is
Question 6 :
In Youngs double slit experiment, a third slit is made in between the double slits. Then
Question 7 :
It is believed that the universe is expanding and hence the distant stars are receding from us. Light from such a star will show
Question 8 :
When the wavelength of light coming from a distant star is measured it is found shifted towards red. Then the conclusion is
Question 10 :
A parallel beam of fast moving electrons is incident normally on a narrow slit. A screen is placed at a large distance from the slit. If the speed of the electrons is increased, which of the following statement is correct
Question 11 :
In the Youngs double slit experiment, the interference pattern is found to have an intensity ratio between bright and dark fringes as 9. This implies that
Question 12 :
Yellow light is used in single slit diffraction experiment with slit width 0.6 mm. If yellow light is replaced by X-rays, then the pattern will reveal that
Question 13 :
An interference pattern was made by using red light. If the red light changes with blue light, the fringes will become
Question 14 :
Interference was observed in interference chamber when air was present, now the chamber is evacuated and if the same light is used, a careful observer will see
Question 15 :
A parallel beam of fast moving electrons is incident normally on a narrow slit. A screen is placed at a large distance from the slit. If the speed of the electrons is increased, which of the following statement is correct?
Question 17 :
Consider the following statements <img style='object-fit:contain' width=9 height=20 src="https://storage.googleapis.com/teachmint/question_assets/NEET/5ea297208ab67a08eba55c8d"> and <img style='object-fit:contain' width=10 height=20 src="https://storage.googleapis.com/teachmint/question_assets/NEET/5ea297a701a30b5955496f96"> and identify the correct answer<br> A. Polarised light can be used to study the helical surface of nucleic acids<br> B. Optics axis is a direction and not any particular line in the crystal
Question 18 :
The sun is rotating about its own axis. The spectral lines emitted from the two ends of its equator, for an observer on the earth, will show
Question 19 :
The dispersive powers of crown and flint glasses are 0.03 and 0.05 respectively. The refractive indices for yellow light for these glasses are 1.517 and 1.621 respectively . It is desired to form an achromatic combination of prisms of crown and flint glasses which can produce a deviation of 1° in the yellow ray. The refracting angle of the flint glass prism is
Question 20 :
A convex lens of crown glass ({tex}n{/tex}=1.525) will behave as a divergent lens if immersed in [CPMT 1984]
Question 21 :
The condition for obtaining secondary maxima in the diffraction pattern due to single slit is
Question 22 :
A point source of light B is placed at a distance L in front of the centre of a mirror of width 'd' hung vertically on a wall. A man walks in front of the mirror along a line parallel to the mirror at a distance 2L from it as shown in fig. The greatest distance over which he can see the image of the light source in the mirror is:<br /><img style='object-fit:contain' src="https://s3.ap-south-1.amazonaws.com/me-p/5f630e9b16d7e6154e4565d8.jpg" />
Question 23 :
When unpolarised light is incident on a plane glass plate at Brewster's angle, then which of the following statements is correct?
Question 24 :
A Young's double slit experiment is conducted in water {tex} \left( \mu _ { 1 } \right) {/tex} as shown in figure. A glass plate of thickness t and refractive index {tex} \mu _ { 2 } {/tex} is placed in the path of {tex} S _ { 2 } {/tex} . The optical path difference at {tex} O {/tex} is<br><img style='object-fit:contain' src="https://storage.googleapis.com/teachmint/question_assets/NEET/5d60f101e5db655bbf10a76e"><br>
Question 25 :
Two light waves superimposing at the mid-point of the screen are coming from coherent sources of light with phase difference {tex} 3\pi {/tex} rad. Their amplitudes are {tex} 1\mathrm { cm } {/tex} each. The resultant amplitude at the given point will be.
Question 26 :
Two coherent point sources {tex} \mathrm { S } _ { 1 } {/tex} and {tex} \mathrm { S } _ { 2 } {/tex} are separated by a small distance d as shown. The fringes obtained on the vertical screen will be:<br><img style='object-fit:contain' src="https://storage.googleapis.com/teachmint/question_assets/NEET/5d60f14bd3eb695bc07eb5f8"><br>
Question 27 :
The diffraction effects in a microscopic specimen become important when the separation between two points is
Question 28 :
Which type of an image is formed by a plane mirror?
Question 29 :
On a hot summer night, the refractive index of air is smallest near the ground and increases with height from the ground. When a light beam is directed horizontally, the Huygens' principle leads us to conclude that as it travels, the light beam:
Question 30 :
A ray is incident at an angle $38^o $ on a mirror. The angle between normal and reflected ray is _________.
Question 31 :
A point source of 100 candela is held 5m above a sheet of blotting paper which reflects 75% of light incident upon it. The illuminance of blotting paper is
Question 32 :
Image formed by a plane mirror is<br/>a) of same size as that of object<br/>b) at the same distance behind the mirror as the object in front<br/>c) erect, virtual<br/>Mark the correct statements:<br/>
Question 33 :
A telescope has an objective of focal length 50 cm and an eye piece of focal length 5 cm. The least distance of distinct vision is 25 cm. The telescope is focused for distinct vision on a scale 200 cm away. The separation between the objective and the eye-piece is[Kerala PET 2002]
Question 34 :
A cubical room is formed with $6$ plane mirror. An insect moves along diagonal of the floor with uniform speed. The velocity of its image in two adjacent walls are $20\sqrt 2 $ cm/s. Then the velocity of image formed by the roof is ;
Question 35 :
The figure shows the interference pattern obtained in a double-slit experiment using light of wavelength {tex}600 \mathrm {nm}{/tex}. {tex} 1,2 {/tex} {tex} 3,4 {/tex} and {tex}5{/tex} are marked on five fringes. The third order bright fringe is<br><img style='object-fit:contain' src="https://storage.googleapis.com/teachmint/question_assets/NEET/5d60f0bee5db655bbf10a710"><br>
Question 36 :
For reflection from air to glass , the value if incident angle for which the reflected light is totally polarised (refractive index = n)
Question 37 :
Which statement is wrong from the following for the reflection by plane mirror?
Question 38 :
In a Young's double slit experiment, the intensity at a point where the path difference {tex}\frac{\lambda}{6}{/tex}({tex}\lambda{/tex} - is wavelength of the light) is {tex}I{/tex}. If {tex}I_{0}{/tex} denotes the maximum intensity, then {tex}\frac{I}{I_{0}}{/tex} is equal to
Question 39 :
In half life of a radio isotope is 2 seconds and number of atoms are only 4, then after one half life remaining (without decay) atoms are probably
Question 40 :
A radioactive nucleus <i>A </i>finally transforms into a stable nucleus <img style='object-fit:contain' src="https://storage.googleapis.com/teachmint/question_assets/NEET/5e901ade1118ef0666af2ecb"> Then <i>A </i>and <i>B</i> can be
Question 41 :
A radioactive nucleus emits a beta particle. The parent and daughter nuclei are
Question 44 :
Electrons are excited form $n=1$ to $n=4$ state. During downward transitions, possible number of spectral lines observed in Balmer series is.
Question 45 :
Total energy of electron in an excited state of hydrogen atom is $-3.4 eV$. The kinetic and potential energy of electron in this state
Question 46 :
Which of the following series in the spectrum of hydrogen atom lies in the visible region of the electromagnetic spectrum?<br>
Question 47 :
Which of the following parameters are the same for all hydrogen-like atoms and ions in their ground states?
Question 48 :
In a radioactive decay reaction:<br>$A\xrightarrow { } B\xrightarrow { } C$<br>Select correct alternative/s t the instant the number of the particles of B is maximum:
Question 49 :
An electron of H-atom de-excites from energy level $n_1=2$ to $n_2=1$ and the emitted photon is incident on $He^+$ ions in ground and first excited state. Which of following transition is possible.
Question 50 :
The transition from the state $n=3$ to $n=1$ in a hydrogen like atom results in ultraviolet radiation. Infrared radiation will be obtained in the transition from-
Question 51 :
The valence of the impurity atom that is to be added to germanium crystal so as to make it a $N-$ type semiconductor, is
Question 52 :
The ionization energy of hydrogen atom is $13.6\ eV$. Hydrogen atoms in the ground state are excited by electromagnetic radiation of energy $12.1\ eV$. How many spectral lines will be emitted by the hydrogen atoms?
Question 53 :
There are only three hydrogen atoms in a discharge tube. The analysis of spectrum shows that in all the hydrogen atoms, electrons are de-exciting from the fourth orbit. What should be the maximum number of spectral lines?<br/>
Question 54 :
If the series limit of Lymen series for hydrogen atom is equal to the series limit of Balmer series for a hydrogen like atom, then atomic number of this hydrogen like atom is
Question 55 :
Match the following :<br/><table class="wysiwyg-table"><tbody><tr><td>Type I</td><td>Type II</td></tr><tr><td>a) Continuous emission spectrum</td><td>e) Tungsten filament of bulb</td></tr><tr><td>b) Line emission spectrum</td><td>f) $CO_2$ gas</td></tr><tr><td>c) Band emission spectrum</td><td>g) Sodium vapour lamp</td></tr><tr><td>d) Line absorption spectrum</td><td>h) chromosphere of sun</td></tr></tbody></table>
Question 56 :
The distance of the closest approach of an alpha particle fired at a nucleus with kinetic energy $K$ is ${r}_{0}$. The distance of the closest approach when the $\alpha$ particle is fired at the same nucleus with kinetic energy $2K$ will be
Question 57 :
If velocity of $\alpha - $particle is made $1/3$ times, then % variation in distance of closest approach will be: (with respect to initial)
Question 58 :
Assertion: Hydrogen atom consists of only one electron but its emission spectrum has many lines.
Reason: Only Lyman series is found in the absorption spectrum of hydrogen atom whereas in the emission spectrum, all the series are found.
Question 59 :
A neutron of energy $1 MeV$ and mass $1.6\times 10^{-27}$ kg passes a proton at such a distance that the angular momentum of the neutron relative to the proton approximately equals $10^{-33}$ J s. The distance of closest approach neglecting the interaction between particles is<br>
Question 60 :
Transfer characteristics output voltage <b>V<sub>0</sub></b> vs input voltage <b>V<sub>1</sub></b> for a base biased transistor in <b>CE</b> configuration is as shown in the figure. For using transistor as a switch, it is used<br><center><img style='object-fit:contain' src="https://storage.googleapis.com/teachmint/question_assets/NEET/5d63bbf423c0625412870d95"></center><br>
Question 61 :
If a PN junction diode of depletion layer width {tex} \mathrm { W } {/tex} and barrier height {tex} \mathrm { V } _ { 0 } {/tex} is forward biased, then
Question 62 :
Assertion: Balmer series lies in the visible region of electromagnetic spectrum.
Reason: $\displaystyle \frac{1}{\lambda} = R \left[\frac{1}{2^2} - \frac{1}{n^2}\right]$, where $n = 3, 4, 5.$
Question 63 :
Let $v_{1}$ be the frequency of the series limited of the Lyman series, $v_{2}$ be the frequency of the first line of the Lyman series, and $v_{3}$ be the frequency of the series limited of the Balmer series. Then:<br/>
Question 64 :
An alpha nucleus of energy $\displaystyle\frac{1}{2}mv^2$ bombards a heavy nuclear target of charge Ze. Then the distance of closest approach for the alpha nucleus will be proportional to
Question 65 :
The ratio of the largest to shortest wavelength in Lyman series of hydrogen spectra is