Via half-life equation we have:
Where the initial amount is 50 grams, half-life is 4 minutes, and time elapsed is 12 minutes. By plugging those values in we get:
There is 6.25 grams left of Ra-229 after 12 minutes.
Answer:
Explanation:
This is case of interference in thin films
for constructive interference in thin film the condition is
2μ t = (2n+1)λ/2 ; μ is refractive index of oil , t is thickness of oil , λ is wave length of light .
2 x 1.28 x t = λ/2 , if n = 0
2 x 1.28 x t = 605 /2
t = 118.16 nm .
the minimum non-zero thickness of the oil film required = 118.16 nm.
Answer:
The electric bill for June is Rs198000
Explanation:
Convert volt to watt, but in order to do so I need to know the amps and since it is not provided I converted if the amps was 1.
I multiple 50 with 10 then with 30 so I know how much watt the fan takes at June.
Since there are 2 light bulb I multiple 10 with 2 than with 8 than with 30.
15000 watts for the fan,
4800 watts for light bulb,
add them and then times it by 10.
Rs198000
Answer:
The emission spectrum is always the same and can be used to identify the element and part of the Bohr model proposed that electrons in the hydrogen are located in particular orbits around the nucleos are True.
Explanation:
The Niels Bohr and quantic mecanic theorys are both based on the study of atomics spectrums. The atomic spectrum is a characteristic pattern of a light wavelenght emited wich is unique to each element.
<u>For example</u>, if we put some low pressure hydrogen in a glass tube and in the tp of the glass we apply a voltage big enough to produce a electric current in the hydrogen gas, the tube its going to emit light wich have a color dependig of the gas element in the interior. If we observe this light with a spectrometer we are going to see shining lines and each one of this lines have a wavelenght and diferent colors. This lines are called emission spectrum and the wavelength of that spectrum are unique to eache element.
<u>Summering up, </u>we can identify elements using the emission spectrum because any element produces the same spectrum than other element.
According to Niels Bhor theory the electron only can be in especific discret ratios to the nucleus. Where this electron moves himself in circukar orbits under the influence of the Coulomb attraction force.
X=15! hope this helps! Also please look at my questions about the cannon ball!!! need help!
