Physics, 24.07.2019 17:30 kendricklamar29

How many photons will be required to raise the temperature of 1.8 g of water by 2.5 k ? '?

Answers: 1

Show answers

Answers

Answer from: deaishaajennings123

Given the following data:

Mass of water = 1.8 grams

Change in temperature = 2.5 Kelvin

Wavelength of infrared = 2.9 x $10^{-4}$ cm.

Specific heat capacity of water = 4.18 J/g°K.

Conversion:

100 cm = 1 m

2.9 x $10^{-4}$ cm = 2.9 x $10^{-6}$ cm

To find the amount of photons required to raise the temperature of 1.8 g of water:

First of all, we would determine the quantity of energy required to raise the temperature of water:

Mathematically, quantity of energy is given by the formula;

$Q = mc\theta$

Where:

Q represents the quantity of energy.m represents the mass of an object.c represents the specific heat capacity.∅ represents the change in temperature.

Substituting the given parameters into the formula, we have;

Q = 1.8(4.18)(2.5)

Q = 18.81 Joules.

Mathematically, the Planck-Einstein relation is given by the formula:

E = hf

Where:

h is Planck constant.f is photon frequency.

To find the photon frequency, we would use this formula:

$Photon\;frequency = \frac{speed}{wavelength} \\\\Photon\;frequency = \frac{3(10^8)}{2.9(10^{-6})}\\\\Photon\;frequency = \frac{300000000}{0.0000029}$

Photon frequency = 1.04 × $10^{14}$ Hertz

Applying Planck-Einstein's relation, we would determine the energy required by each of photon:

E = 6.626 × $10^{-34}$ × 1.04 × $10^{14}$

E = 6.89 × $10^{-20}$ Joules

Now, we can calculate the amount of photons required to raise the temperature of 1.8 g of water by using this expression:

$Number\;of\;photons = \frac{Q}{E} \\\\Number\;of\;photons = \frac{18.81}{6.89(10^{-20})}$

Number of photons = 2.73 × $10^{20}$ photons.

Read more: link

Complete Question:

Water is exposed to infrared radiation of wavelength 2.9x10-4 cm. Assume that all the radiation is absorbed and converted to heat. How many photons will be required to raise the temperature of 1.8 g of water by 2.5 K? Express your answer using two significant figures.

Answer from: chonawilson4

Missing part in the text of the problem:
"Water is exposed to infrared radiation of wavelength 3.0×10^−6 m"

First we can calculate the amount of energy needed to raise the temperature of the water, which is given by
$Q=m C_s \Delta T$
where
m=1.8 g is the mass of the water
C_s = 4.18 J/(g K)

is the specific heat capacity of the water
$\Delta T=2.5 K$ is the increase in temperature.

Substituting the data, we find
Q=(1.8 g)(4.18 J/(gK))(2.5 K)=18.8 J=E

We know that each photon carries an energy of
E_1 = hf

where h is the Planck constant and f the frequency of the photon. Using the wavelength, we can find the photon frequency:
$\lambda = \frac{c}{f}= \frac{3 \cdot 10^8 m/s}{3 \cdot 10^{-6} m}=1 \cdot 10^{14}Hz$

So, the energy of a single photon of this frequency is
$E_1 = hf =(6.6 \cdot 10^{-34} J)(1 \cdot 10^{14} Hz)=6.6 \cdot 10^{-20} J$

and the number of photons needed is the total energy needed divided by the energy of a single photon:
$N= \frac{E}{E_1}= \frac{18.8 J}{6.6 \cdot 10^{-20} J} =2.84 \cdot 10^{20} photons$

Answer from: Quest

e/c, where e is its total energy

Answer from: Quest

Your answer would be false

Another question on Physics

Physics, 21.06.2019 22:30

Select the word from the list that best fits the definition classification of most stars on the h-r diagram

Answers: 1

Answer

Physics, 22.06.2019 00:40

Electroplating is a way to coat a complex metal object with a very thin (and hence inexpensive) layer of a precious metal, such as silver or gold. in essence the metal object is made the cathode of an electrolytic cell in which the precious metal cations are dissolved in aqueous solution. suppose a current of 480.ma is passed through an electroplating cell with an aqueous solution of agno3 in the cathode compartment for 46.0 seconds. calculate the mass of pure silver deposited on a metal object made into the cathode of the cell. round your answer to 3 significant digits. also, be sure your answer contains a unit symbol. ×10μ

Answers: 3

Answer

Physics, 22.06.2019 03:30

Two polarizers are oriented at 24.0∘ to one another. light polarized at a 12.0-degree angle to each polarizer passes through both. what is the transmitted intensity (%)?

Answers: 2

Answer

Physics, 22.06.2019 10:50

Two rigid transformations are used to map δhjk to δlmn. the first is a translation of vertex h to vertex l. what is the second transformation? a reflection across the line containing hk a rotation about point h a reflection across the line containing hj a rotation about point k