Answer:
D. 13
Explanation:
For most elements other than hydrogen, isotopes are named for their mass number. For example, carbon atoms with the usual 6 neutrons have a mass number of 12 (6 protons + 6 neutrons = 12), so they are called carbon-12. Carbon atoms with 7 neutrons have an atomic mass of 13 (6 protons + 7 neutrons = 13).
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Answer:
The observed wavelength is
(color - Red)
Explanation:
From the question we are told that
The wavelength of the emitter is ![\lambda_ e = 500 nm = 500 *10^{-9} \ m](https://tex.z-dn.net/?f=%5Clambda_%20e%20%20%3D%20500%20nm%20%20%3D%20%20500%20%2A10%5E%7B-9%7D%20%5C%20%20m)
The redshift is R = 0.4
Generally red shift is mathematically represented as
![R = \frac{ \lambda - \lambda_e }{\lambda_e}](https://tex.z-dn.net/?f=R%20%3D%20%20%5Cfrac%7B%20%5Clambda%20-%20%20%5Clambda_e%20%7D%7B%5Clambda_e%7D)
=> ![0.4 = \frac{ \lambda - 500 *10^{-9} }{500 *10^{-9} }](https://tex.z-dn.net/?f=0.4%20%20%3D%20%20%5Cfrac%7B%20%5Clambda%20-%20%20%20500%20%2A10%5E%7B-9%7D%20%7D%7B500%20%2A10%5E%7B-9%7D%20%7D)
=> ![\lambda - 500*10^{-9} = 200*10^{-9}](https://tex.z-dn.net/?f=%20%5Clambda%20-%20500%2A10%5E%7B-9%7D%20%3D%20200%2A10%5E%7B-9%7D%20%20)
=> ![\lambda = 700 *10^{-9}](https://tex.z-dn.net/?f=%20%5Clambda%20%3D%20700%20%2A10%5E%7B-9%7D)
=> ![\lambda = 700nm](https://tex.z-dn.net/?f=%20%5Clambda%20%3D%20700nm)
It's the second graph!
it's the only one with a negative gradient.
so the temperature of the ball will fall in water as it looses its heat.
activate windows,:-P