# What is the energy of a photon emitted with a wavelength of 571 nm?

Answer: E=h * nu, where nu is frequency of the wave.
frequency = 1/wavelength = 1/571 *10 ^-9 = 1.7 * 10^7.

e= 6.63 *10^-34 *1.7 *10^7

e=11.271 * 10^-27 Joules

## Related Questions

an unknown compound was determined to be 74.97% carbon, 8.39% hydrogen, and 16.64% oxygen. calculate the empirical formula

C₆H₈O

Explanation:

Empirical Formula: This is the simplest formula of a compound.

From the question,

Percentage by mass of the elements: C = 74.97%, H = 8.39%, O = 16.64%

Molar mass of the elements : C = 12 g/ mole, H = 1 g/mole, O = 16 g/mole

Step 1: Divide the percentage by mass by the molar mass

C                       :         H                   :           O

74.97/12                   8.39/1                     16.64 /16

6.2475               :       8.39                :          1.04

Step 2: Dived by the smallest ratio ( 1.04)

C                         :        H                   :              O

6.2475/1.04        :      8.39/1.04        :              1.04/1.04

6                          :      8                     :               1

Hence, The empirical formula of the compound = C₆H₈O

The empirical formula of the unknown compound is C₆H₈O

Explanation:

The simplest ratio (whole number) of the atoms in a compound is the empirical formula of the compound.

To determine the empirical formula of the compound given, the following steps are followed;

(i). Since percentage compositions of the elements in the compound are given, it can be assumed that all calculated from 100 grams of the compound. Therefore, the percentages can be changed directly to grams as follows;

74.97% Carbon (C) => 74.97g of Carbon (C)

8.39% Hydrogen (H) => 8.39g of Hydrogen (H)

16.64% Oxygen (O) => 16.64g of Oxygen (O)

(ii) Convert the grams to corresponding number of moles;

Recall that;

1 mole of Carbon contains 12 grams of the atom

=> 74.97 grams will be   moles of Carbon

=> 74.97 grams will be  6.2475 moles of Carbon

Also,

1 mole of Hydrogen atoms contains 1 gram of the atom

=> 8.39 grams will be   moles of Hydrogen

=> 8.39 grams will be  8.39 moles of Hydrogen

And,

1 mole of Oxygen atoms contains 16 grams of the atom

=> 16.64 grams will be   moles of Hydrogen

=> 16.64 grams will be  1.04 moles of Hydrogen

(iii) Normalize the results calculated in step (ii) above by dividing each by the smallest (which is 1.04)

|     Carbon          |     Hydrogen         |         Oxygen

Moles                      |      6.2475          |      8.39                 |          1.04

Divide by smallest |     = 6.007  |        = 8.07       |           = 1

(iv) Round off the results in (iii) above to the nearest unit

|     Carbon          |     Hydrogen         |         Oxygen

Moles                      |      6.2475          |      8.39                 |          1.04

Divide by smallest |     = 6.007  |        = 8.07       |           = 1

Rounding off          |       6                   |        8                    |           1

(v) Derive the empirical formula

By using the numbers resulting from step (iv) as subscript, place them beside each of their corresponding elements as follows;

=> C₆H₈O₁

The number 1 (which is the subscript of Oxygen can be removed)

=> C₆H₈O

Therefore, the empirical formula of the unknown compound is C₆H₈O

Which gas law states that the pressure of a gas decreases when volume is increased and the temperature is unchanged? A. Charles' Law
B. Boyle's Law
C. The General Gas Law
D. The Law of Cubic Expansion

Which gas law states that the pressure of a gas decreases when volume is increased and the temperature is unchanged?

A. The General Gas Law

B. The Law of Cubic Expansion

C. Charles' Law

D. Boyle's Law

A horizontal surface of area 0.321 m2has an electric flux of 123 N.m2/C passing through it at an angle of 25° to the horizontal. If the flux is due to a uniform electric field, calculate the magnitude of the latter.

electric filed is 907 N/C

Explanation:

Given data

surface of area = 0.321 m²

electric flux of 123 N.m²/C

angle = 25°

to find out

magnitude of the electric field

solution

we know flux formula that is

flux = electric filed × area

put all value

123 = electric filed × 0.321 sin(25)

electric filed = 123 /  0.321 sin(25)

electric filed = 906.67

so electric filed is 907 N/C

Some species of jellyfish use jet propulsion to get around, a much gentler form of jet propulsion than squid use. A small jellyfish takes water into its bell; the total mass of jellyfish and water is 3.2 g. It then rapidly ejects 1.3 g of water, achieving a speed of 0.070 m/s. What is the speed of the ejected water?

speed of ejected out water will be 0.102 m/s

Explanation:

Initially the jellyfish is given at rest

so here since there is no external force on the system of jelly fish and the water in it so the momentum of the whole system will remains conserved

so here we have

initial momentum is zero

now final momentum of both will also be zero

so here we have

so we have

so speed of ejected out water will be 0.102 m/s

What were the results of European colonization of central Africa? A. Africans were forced to work on plantations.

B. Europeans controlled the government of central Africa.

C. European countries made little economic gain from the colonies.

D. Millions of Africans died in the Congo due to mistreatment.

Note: this is a multiple choice questions.

Africans were forced to work on plantations and millions of Africans died in the Congo due to mistreatment were the results of European colonization of central Africa.

Results of European colonization of central Africa

Colonialism creates a large impact on the lives of Africans. They were made labours which work for eurpeans for the plantation. Millions of african people died due to bad treatment of Europeans.

So we can conclude that option A and D are correct answers.

Planting of crops to purify -lucern, shrubs, trees(possible job creation)

Those plants was used to clean toxic substance in the environment

In our current time, those crops had became a very important commodity and could potentially be used to generate profit if you handle it seriously an created several job opportunities in the process

hope this helps

Plants are a noteworthy method for water decontamination. Plants, for example, Lucerne and bushes have a high affinity for water. They retain water from the dirt together with the contaminants.

Further Explanation

Purification of water using plants

The purification of water from plants is the same old thing. The earth is continually utilizing both soil and vegetation to wash down itself. Water is a functioning liquid. It is consistently moving and is being used by plants, soil, mists, truly everything. As water ignores through and plants roots and leaves, the fluid is ingested into the plant's tissues. There is a characteristic cycle wherein water is first ingested then discharged from the plant's leaves and roots.

Such plants, for example, Reed, Bur-Reed, Sedges, Water Lily, etc.

Sweet flag and water soldier have the ability to reuse water through their root system.

Using plants purifying of water from wastes

Plants remove from water

1. Heavy metals
2. Parasites
3. Harmful microorganisms
4. Radio dynamic isotopes (permeable carbon and green coal work much superior to plants).
5. Chemicals

Cysts (with time (the sores pull in themselves to the plant roots with a delayed introduction (this technique isn't 100%).

Obviously, once the contaminants are consumed by the plants many will address how to discard them.

To begin with, a portion of the consumed waste will normally break down with the plant. In any case, synthetic compounds, radio dynamic isotopes, and overwhelming metals will require exceptional treatment when the plants kick the bucket.

Another technique for dealing with this plant waste is to utilize mushroom spores. Mushrooms produce a slim threadlike system of roots called mycelium and mycelium produces compounds that separate a considerable number of "nasties" (contaminants). So basically, we utilize a plant to clean a plant.

Subject: Physics

Level: High School

Keywords

• Purification of water using plants
• Purification of water using plants

How does the frequency of sound relate to its pitch?

Good afternoon!
the answer to that particular question is this
rule
a particular pitch directly corresponds to frequency in that if you have a pitch you will have a high frequency
if you a low frequency you will have a low pitch
both are intertwined in marriage!

Please help fast!! A skateboarder traveling at 10.4 m/s starts getting chased by a grumpy dog. The skateboarder speeds up with a constant acceleration for 39m over a 3.3s. We want to find the acceleration of the skateboarder over the 3.3s time interval.

Which kinematic formula would be most useful to solve for the target unknown?

A. V= Vo+a(t)
B. X= (V+Vo/2)t
C. X= Vo(t)+1/2at^2
D. V^2 = Vo^2 +2ax
E. X= vt-1/2at^2