Download App

Bohr’s Model and Physics of Atom — Physics STD 12 Science — Question

Rajasthan BoardEnglish MediumSTD 12 SciencePhysicsBohr’s Model and Physics of Atom2 Marks
Question
A spectroscopic instrument can resolve two nearby wavelengths $\lambda$ and $\lambda+\Delta\lambda$ if $\frac{\lambda}{\Delta\lambda}$ is smaller than 8000. This is used to study the spectral lines of the Balmer series of hydrogen. Approximately how many lines will be resolved by the instrument?
✓

Answer

The range of Balmer series is 656.3nm to 365nm. It can resolve $\lambda$ and $\lambda+\Delta\lambda$ if $\frac{\lambda}{\Delta\lambda}=8000$
$\therefore$ No. of wavelength in the range $=\frac{656.3-365}{8000}=36$
Total no. of lines 36 + 2 = 38 [extra two is for first and last wavelength]

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

Explore more

More "2 Marks Questions" from Bohr’s Model and Physics of Atom→Bohr’s Model and Physics of Atom — all question types→Physics STD 12 Science question papers→Rajasthan Board STD 12 Science question papers→Rajasthan Board question paper generator→

Similar questions

A bulb is hanging over a table. At which portion of the table is the illuminance maximum? If a plane mirror is placed above the bulb facing the table, will the illuminance on the table increase?
→
What is called equipotential surface? Draw equipotential surfaces for point charges and write their properties.
→
For two metallic plates $P$ and $Q$, the curves between stopping potential and threshold frequency are drawn. Which of these metal will have higher threshold frequency and wavelength?
Image
→
Each of the resistances shown in figure. has a value of $20\Omega.$ Find the equivalent resistance between A and B. Does it depend on whether the point A or B is at higher potential?
→
Can virtual image be formed on the retina in a seeing process?
→
Calculate the orbital period of the electron in the first excited state of hydrogen atom.
→
Find the thermo-emf developed in a copper$-$silver thermocouple when the junctions are kept at $0^\circ C$ and $40^\circ C$. Use the data in table.
 
Metal with
$a$
$b$
lead $(Pb)$
$\mu\text{V}/^\circ\text{C}$
$\mu\text{V}/^\circ(\text{C})^2$
Aluminium
 $-0.47$ $0.003$
Bismuth
 $-43.7$ $-0·47$
Copper
 $2.76$ $0·012$
Gold
 $2.90$ $0.0093$
Iron
 $16.6$ $-0.030$
Nickel
 $19.1$ $-0.030$
Platinum
 $-1.79$ $-0.035$
Silver
 $2.50$ $0.012$
Steel
 $10.8$ $-0.016$
 
→
Explain $($or write a short note on$)$ capacitors and capacitance.
→
Explain with example why matter particle acquires electric charge.
→
Water flows through the tube shown in The areas of cross$-$section of the wide and the narrow portions of the tube are $5\ cm^2$ and $2\ cm^2$ respectively. The rate of flow of water through the tube is $500\ cm^3/s.$ Find the difference of mercury levels in the $U-$tube.
→