Explanation :
When an electron jumps from one energy level to another, the energy of atom gets changed.
If a photon gets absorbed, the electron will move to higher energy levels and then fall back to the lower energy levels. Then each time a photon will be absorbed whose energy is given by difference between the initial and final energy levels i.e
In Balmer series, the transition is from higher energy levels to n = 2.
So, the necessary condition for Balmer series is that the electron should be at first excited state or n = 2 level as shown in figure.
Answer:
371.2 mm
Explanation:
The Balmer series of spectral lines is obtained from the formula
1/λ = R(1/2² -1/n²) where λ = wavelength, R = Rydberg's constant = 1.097 × 10⁷ m⁻¹
when n = 15
1/λ = 1.097 × 10⁷ m⁻¹(1/2² -1/15²)
= 1.097 × 10⁷ m⁻¹(1/4 -1/225)
= 1.097 × 10⁷ m⁻¹(0.25 - 0.0044)
= 1.097 × 10⁷ m⁻¹ 0.245556
= 2.693 10⁶ m⁻¹
So,
λ = 1/2.693 10⁶ m⁻¹
= 0.3712 10⁻⁶ m
= 371.2 mm
The definition of speed is (distance covered) / (time to cover the distance) .
So a unit of speed has to be (a unit of length) / (a unit of time) .
Here are several perfectly fine units of speed:
-- miles per hour
-- feet per second
-- meters per second
-- kilometers per hour
-- inches per second
-- centimeters per minute
-- yards per Century
-- furlongs per fortnight
-- nanometers per microsecond
-- Smoots per week
-- parsecs per millenium
Answer:
An ion is an atom or group of atoms with a positive or negative charge. Ions form when atoms lose or gain electrons to obtain a full outer shell: metal atoms lose electrons to form positively charged ions non-metal atoms gain electrons to form negatively charged ions.
Explanation:
Answer:
Number of slices of pizza is 993.
Explanation:
It is given that, in one slice of "everything" pizza there are 650 Calories. The conversion factor from calories to joules is :
1 calorie = 4.184 joules
650 calories = 2719.6 joules
Total energy in the pizza, E = 2700000 J
Let there are n number of slices of pizza. It is given by :
n = 992.79
or
n = 993
So, there are 993 slices of pizza. Hence, this is the required solution.