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 sodium-vapor lamp has a power output of 10 W. Using 589.3 nm as the average wavelength of the source, calculate the number of photons emitted per second.

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?

How do we know that photons possess wave-like properties?

Let p and q represent the following simple statements: p: This is an alligator. q: This is a reptile. Write each compound statement in symbolic form. Being a reptile is necessary for being an alligator.

How many $550 \mathrm{~nm}$ photons would have to be absorbed to raise the temperature of $1.0 \mathrm{~g}$ of water by $1.0^{\circ} \mathrm{C}$ ?

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?

A satellite in Earth orbit maintains a panel of solar cells of area

$$2.90 m^2$$

perpendicular to the direction of the Sun's light rays. The intensity of the light at the panel is

$$1.39 \mathrm { kW } / \mathrm { m } ^ { 2 }$$

. (a) At what rate does solar energy arrive at the panel? (b) At what rate are solar photons absorbed by the panel? Assume that the solar radiation is monochromatic, with a wavelength of 550 nm, and that all the solar radiation striking the panel is absorbed. (c) How long would it take for a "mole of photons" to be absorbed by the panel?

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.

A pulsed laser emits light in a series of short pulses, each having a duration of 25.0 ms. The average power of each pulse is 5.00 mW, and the wavelength of the light is 633 nm. Find (a) the energy of each pulse and (b) the number of photons in each pulse.

A pulsed argon laser of 476.5-nm wavelength emits $3.0 \times 10^{-3} \mathrm{J}$ of energy to produce a tiny weld to repair a detached retina. How many photons are in the laser pulse?

Sunlight reaching the Earth's atmosphere has an intensity of about $1300 \mathrm{~W} / \mathrm{m}^2$. Estimate how many photons per square meter per second this represents. Take the average wavelength to be $550 \mathrm{~nm}$.

A photon strikes a metal with a work function $\phi$ and produces a photoelectron with a de Broglie wavelength equal to the wavelength of the original photon. (b) If one of these photons strikes platinum $(\phi=6.35 \mathrm{eV})$, determine the resulting maximum speed of the photoelectron that is emitted.

How is the irony of the necklace symbolic of a larger irony in Mathilde's life? Explain, citing examples from the story.