Which landscape is located at 42°N 75° W

How is radiation related to electromagnetic waves and thermal energy?

Daniel [21]

Well, radiation, in terms of physics, is the emission of electromagnetic waves

now, electromagnetic waves can take many different forms like visible light, radio waves, gamma radiation, ultraviolet light. Depending on its wavelength or frequency

thermal energy or heat generally takes the form of infrared light and all light is an form of electromagnetic wave

7 0

3 years ago

A tank contains 200 gallons of water in which 300 grams of salt is dissolved. A brine solution containing 0.4 kilograms of salt

Nadusha1986 [10]

Answer:

<h3>Therefore, after long period of time 80kg of salt will remain in tank</h3>

Explanation:

given amount of salt at time t is A(t)

initial amount of salt =300 gm =0.3kg

=>A(0)=0.3

rate of salt inflow =5*0.4= 2 kg/min

rate of salt out flow =5*A/(200)=A/40

rate of change of salt at time t , dA/dt= rate of salt inflow- ratew of salt outflow

$dA/dt=2-(A/40)\\\\dA=2dt-(A/40)dt\\\\dA+(A/40)dt=2dt$

integrating factor

$=e^{\int\limits (1/40) \, dt}$

integrating factor $=e^{(1/40)t}$

multiply on both sides by $=e^{(1/40)t}$

$dAe^{(1/40)t}+(A/40)e^{(1/40)t} dt =2e^{(1/40)t}t\\\\(Ae^{(1/40)t})=2e^{(1/40)t}t$

integrate on both sides

$\int\limits(Ae^{(1/40)t})=\int\limits2e^{(1/40)t}dt\\\\(Ae^{(1/40)t})=2*40e^{(1/40)t}+C\\\\A=80+(C/e^{(1/40)t})\\\\A(0)=0.3\\\\0.3=80+(C/e^{(1/40)t}^*^0)\\\\0.3=80+(C/1)\\\\C=0.3-80\\\\C=-79.7\\\\A(t)=80-(79.7/e^{(1/40)t})$

b)

after long period of time means t - > ∞

${t \to \infty}\\\\ \lim_{t \to \infty} A_t \\\\ \lim_{t \to \infty} (80)-(79/{e^{(1/40)t}}\\\\=80-(0)\\\\=80$

<h3>Therefore, after long period of time 80kg of salt will remain in tank</h3>

6 0

2 years ago

Consider a transition of the electron in the hydrogen atom from n=3 to n=7.

kow [346]

<u>Answer:</u>

<u>For a:</u> The wavelength of light is $1.005\times 10^{-6}m$

<u>For b:</u> The light is getting absorbed

<u>Explanation:</u>

<u>For a:</u>

To calculate the wavelength of light, we use Rydberg's Equation:

$\frac{1}{\lambda}=R_H\left(\frac{1}{n_i^2}-\frac{1}{n_f^2} \right )$

Where,

$\lambda$ = Wavelength of radiation

$R_H$ = Rydberg's Constant = $1.097\times 10^7m^{-1}$

$n_f$ = Higher energy level = 7

$n_i$ = Lower energy level = 3

Putting the values in above equation, we get:

$\frac{1}{\lambda }=1.097\times 10^7m^{-1}\left(\frac{1}{3^2}-\frac{1}{7^2} \right )\\\\\lambda =1.005\times 10^{-6}m$

Hence, the wavelength of light is $1.005\times 10^{-6}m$

<u>For b:</u>

There are two ways in which electrons can transition between energy levels:

<u>Absorption spectra:</u> This type of spectra is seen when an electron jumps from lower energy level to higher energy level. In this process, energy is absorbed.
<u>Emission spectra:</u> This type of spectra is seen when an electron jumps from higher energy level to lower energy level. In this process, energy is released in the form of photons.

As, the electron jumps from lower energy level to higher energy level. The wavelength is getting absorbed.

6 0

3 years ago

The ph of a solution containing 0.818 M acetic acid<br> (ka1.76*10-5) ans 0.172 M sodium acetate is?

kvasek [131]

Explanation:

It is known that the relation between pH and $pK_{a}$ is as follows.

pH = $pK_{a} + log \frac{[salt]}{[acid]}$

and, $pK_{a} = -log K_{a}$

Hence, first we will calculate the value of $pK_{a}$ as follows.

$pK_{a} = -log K_{a}$

= $-log (1.76 \times 10^{-5}$

= 4.75

Now, we will calculate the value of pH as follows.

pH = $pK_{a} + log \frac{[\text{sodium acetate}]}{\text{acetic acid}}$

= $4.75 + log \frac{0.172}{0.818}$

= 4.75 + (-0.677)

= 4.07

Therefore, we can conclude that the pH of given solution is 4.07.

5 0

3 years ago

After standardizing a NaOH solution, you use it to titrate an HCl solution known to have a concentration of 0.203 M. You perform

jek_recluse [69]

Answer:

0.203 is the mean of the concentration of the HCl solution

Explanation:

You have 5 concentrations. The most appropiate result is the mean of those results. The mean is a statistical defined as the sum of each result divided by the total amount of results. For the results of the problem, the mean is:

0.210 + 0.204 + 0.201 + 0.202 + 0.197 = 1.014 / 5 =

<h3>0.203 is the mean of the concentration of the HCl solution</h3>

8 0

2 years ago