How much energy (in kj) do 3.0 moles of photons, all with a wavelength of 670 nm, contain?

In a beam of white light (wavelengths from 400 to 750 $\mathrm{nm}$ ), what range of momentum can the photons have?

In Exercises, use a symbolic differentiation utility to analyze the graph of the function. Label any extrema and/or asymptotes that exist.

$f(x)=\frac{x^2}{x^2-1}$

Calculate the energies of photons related to the two lines using the relationships expressed in the following equations. $E_{\text {photon }}=h v ; c=\lambda v ; E=h c / \lambda$

A pulsed ruby laser emits light at 694.3 nm. For a 14.0-ps pulse containing 3.00 J of energy, find the number of photons in it.

Photon 1 has wavelength $\lambda_1$ and photon 2 has wavelength $\lambda_2=2 \lambda_1$. What is the energy ratio $E_2 / E_1$ of the two photons?

Suppose a starship had a mass of $1.25 \times 10^{9}\ \mathrm{kg}$ and was initially at rest. If its "matter-antimatter engines" produced photons from electron-positron annihilation and focused them to travel backward out from the ship, how many photons would they have to emit to reach 0.100% of the speed of light?

A random sample of $n=100$ measurements has been selected from a population with unknown mean $\mu$ and known standard deviation $\sigma=10$. Calculate the width of the confidence interval for $\mu$ for the confidence levels given in the exercise. What effect do the changing confidence levels have on the width of the interval? $95 \%(\alpha=.05)$

Find the product.

$$\left(6 b^2-6\right)\left(4 b^2-4\right)$$

Estimate the number of photons emitted per second from $1.0 \mathrm{cm}^{2}$ of a person’s skin if a typical emitted photon has a wavelength of 10,000 nm.

The human body has a surface area of approximately $1.8 \mathrm{m}^{2}$, a surface temperature of approximately $30^{\circ} \mathrm{C}$, and a typical emissivity at infrared wavelengths of e = 0.97. If we make the approximation that all photons are emitted at the wavelength of peak intensity, how many photons per second does the body emit?

What are the literal and symbolic meanings of each character or object from the allegory? Use a chart like this one to record your answers.

A carbon dioxide laser emits $5.0 \times 10^{22}$ photons $/ \mathrm{s}$ at an infrared wavelength of $10.6 \mu \mathrm{m}$. What is the laser's power output?

Due to momentum considerations, pair annihilation cannot result in the emission of how many photons: (a) one, (b) two, (c) three, or (d) four?