An electrom in the hydrogen atom makes a transition from
amenergy state of principal quantum numbers ni to the
n=2state. if the photon emitted has a wave length of 434nm, what
isthe value of ni?

ni = approx 1

Explanation:

speed of light c = fλ where is the the corresponding frequency and  λ is the wavelength.

λ = 434 nm, 1 nm =  1/ 10⁹ m

3.00 × 10⁸ m/s = (434 / 10 ⁹) m × f

f = 3.00 × 10⁸ × 10⁹) / 434 = 6.9124 × 10 ¹⁴ Hz

Energy = hf where h is planck constant = 6.62 × 10⁻³⁴ J.s

E = 6.62 × 10⁻³⁴ J.s × 6.9124 × 10 ¹⁴ Hz = 4.76 × 10⁻¹⁹J

In a hydrogen atom, the energy of the photon emitted can be calculated using the formula below:

ΔE = RH ( 1/ ni² - 1/nf²)

4.76 × 10⁻¹⁹J  = 2.18 × 10⁻¹⁸ J ( 1/ ni² - 1/nf²)

(4.76 × 10⁻¹⁹J) / (2.18 × 10⁻¹⁸ J) = ( 1/ ni² - 1/nf²)

0.21835 = 1/ni² - 1/ 2²

0.21835 + 0.25 = 1/ni²

0.46835 = 1/ni²

ni² = 1 / 0.46835 = 2.135155

ni = √2.135155 = 1.46  approx 1

8 m/s because for him to get the same amount of energy as ray is putting out, bobby, who weighs half as much as ray, needs to run twice as fast.

most historians agree that gabriel mouton, the vicar of st. paul’s church in lyons, france, is the “founding father” of the metric system. he proposed a decimal system of measurement in 1670. mouton based it on the length of one minute of arc of a great circle of the earth (now called a nautical mile, 1852 meters). he also proposed the swing-length of a pendulum with a frequency of one beat per second as the unit of length (about 25 cm). a pendulum beating with this length would have been fairly easy to produce, thus facilitating the widespread distribution of uniform standards. over the years, his work was revised, improved, and extended by a number of french scientists.

the political sponsor of weights and measures reform in the french revolutionary national assembly was the bishop of autun, better known as talleyrand. under his auspices, the french academy appointed several committees to carry out the work of developing a usable system of weights and measures for france. one of the committees recommended a decimalized measurement system based upon a length equal to one ten-millionth of the length of a quadrant of the earth’s meridian (i.e., one ten-millionth of the distance between the equator and the north pole).