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Who discovered the Balmer formula for a series of hydrogen emission lines?

A

Russell-Saunders

B

Johannes Rydberg

C

Johann Balmer

D

Walter Ritz

Correct Answer: Johann Balmer

In 1885, Johann Balmer, a Swiss mathematician, discovered the Balmer formula for a series of hydrogen emission lines. Later, some changes were done by Johannes Rydberg and Walter Ritz in the formula whereas Russell-Saunders is also known as L-S coupling.

If the wavelength of the first line of the Balmer series in the hydrogen spectrum is $$\lambda $$, then the wavelength of the first line of the Lyman series is

A

$$\frac{{27}}{5}\lambda $$

B

$$\frac{5}{{27}}\lambda $$

C

$$\frac{{32}}{{27}}\lambda $$

D

$$\frac{{27}}{{32}}\lambda $$

RH রিডবার্গ ধ্রুবক হলে, হাইড্রোজেন বর্ণালির বামার সিরিজের ২য় লাইনের তরঙ্গদৈর্ঘ্য কত হবে? ( If RH is the Rydberg constant, what will be the wavelength of the 2nd line in the Balmer series of hydrogen spectrum?)

A

36RH5

B

163RH

C

3RH16

D

536RH

Which of the following will be the longest wavelength in Balmer series of hydrogen atom?

A

2300 Å

B

1215 Å

C

4800 Å

D

6557 Å

Consider the following statements.
1. Magnetic lines of force are closed curves while electric lines are not.
2. Electric lines of force are closed curves while magnetic lines are not.
3. Both electric and magnetic lines of force are closed curves.
Which of statement(s) given above is/are correct?

A

Only 2

B

Both 1 and 2

C

Only 1

D

1, 2 and 3

The ultraviolet spectral region is obtained in Balmer series.

A

True

B

False

Arrange the following stages in a sequence, such that they result in an ogee curve between two parallel lines AB and CD, such that they are the tangents to the arc. m) Join the adjacent ends B and C with a straight line. n) Divide the line BC into four parts using the points P1, P2, P3. o) Draw lines such that they pass through the points P1, P2, P3, and are perpendicular to the line BC. p) Draw the perpendicular lines through the points B and C such that they cut the lines passing through P1, P3 respectively at E and F. q) With the center E draw an arc BP2 and with center F draw an arc P2C, thus arc BP2C is required ogee curve.

A

m, n, o, p, q

B

m, o, p, q, n

C

m, n, p, q, o

D

p, q, o, n, m

In a Plane there are 37 straight lines, of which 13 pass through the point A and 11 pass through the point B. Besides, no three lines pass through one point, no lines passes through both points A and B , and no two are parallel. Find the number of points of intersection of the straight lines.

A

525

B

535

C

545

D

555

Consider the following statements regarding synthetic varieties
1. Parental materials are always inbred lines.
2. Open pollinated materials are also used as parental lines.
3. There is no limit on the number of parental lines used.
4. Parental lines are always tested for their combining ability.
Which of the statements given above is/are correct?

A

1 and 3

B

2 and 4

C

1 and 4

D

3 and 4

Hydrogen atom is excited from ground state to another state with principal quantum number equal to 4. Then the number of spectral lines in the emission spectra will be

A

2

B

6

C

5

D

3

Select a figure from amongst the Answer Figures which will continue the same series as established by the five Problem Figures.

A

1

B

2

C

3

D

4

E

5