HW Question #4

[Lillie Yazdi 3J]

A liquid is exposed to infrared radiation with a wavelength of 8.78×10−4 cm.
Assume that all the radiation is absorbed and converted to heat. How many photons are required for the liquid to absorb 46.65 J
of heat?

I've done this problem so many times yet I can't find the right answer even though I've been doing the correct process. Can anyone explain to me how they solved it so I can see what I'm doing wrong?

[Nicolas Zarco 2K]

First, you should convert cm to m, and then you use the equation c = λv to find the frequency which you can use to find the energy for each photon with E = hv. Divide the energy required by the amount of energy per photon to find out how many photons are required.

[Kevin Zhang 3K]

I first convert the wavelength to frequency to get the energy of a photon. From there, I divide the 46.65 J by the energy of the photon

edit. i forgot to make sure all units are SI units so make it m

[Hailey Jeon]

You should try to determine the energy of a single photon using the equation E(photon) = hc/λ
After determining the E(single photon), divide 46.65J with the E(single photon) value.

[Zinnia Kwan 3D]

First of all, start off by calculating the energy of one photon using E= hc/λ. (make sure you convert cm to meters!).
This would get u to E=1.745 x 10^-30.

Then you just have to divide 46.65 J by the energy of one photon calculated above to get total number of photons.

[Lillie Yazdi 3J]

First of all, start off by calculating the energy of one photon using E= hc/λ. (make sure you convert cm to meters!).
This would get u to E=1.745 x 10^-30.

Then you just have to divide 46.65 J by the energy of one photon calculated above to get total number of photons.

I did that and it's still saying I'm wrong :(

[Sophia Dominguez 3I]

First, you need to convert the wavelength from cm to m. Then, you can use the equation E(photon) = hc/λ where c is the speed of light, λ is the wavelength in meters, and h is Planck’s constant. You would use this equation to find the energy of the photon. Then, divide the given heat value by the energy of one photon calculated to get the number of photons required.