What is electromagnetic radiation? Give some examples of such radiation. Explain what the wavelength $(\lambda)$ and frequency $(\nu)$ of electromagnetic radiation represent. Sketch a representation of a wave and indicate on your drawing one wavelength of the wave. At what speed does electromagnetic radiation move through space? How is this speed related to $\lambda$ and $\nu$ ?

The diameter and surface emissivity of an electrically heated plate are D=300 mm and $\varepsilon=0.80$, respectively. (a) Estimate the power needed to maintain a surface temperature of $200^{\circ} \mathrm{C}$ in a room for which the air and the walls are at $25^{\circ} \mathrm{C}$. The coefficient characterizing heat transfer by natural convection depends on the surface temperature and, in units of $\mathrm{W} / \mathrm{m}^{2} \cdot \mathrm{K}$, may be approximated by an expression of the form $h=0.80\left(T_{s}-T_{\infty}\right)^{1 / 3}$. (b) Assess the effect of surface temperature on the power requirement, as well as on the relative contributions of convection and radiation to heat transfer from the surface.

Lukas had contracted Wilson's Roofing to replace the roof on his home. Before they finished the job, Lukas suffered water damage to his carpet from a leak in the roof. To make up for the inconvenience, he decided to claim that his sofa and recliner had also been damaged by water. The company agreed to replace the items immediately and apologized for the mishap.

Should Lukas be entitled to any compensation for his inconvenience resulting from the water damage to his carpet?

A transverse wave pulse travels to the right along a string with a speed $v=2.4 \mathrm{~m} / \mathrm{s}$. At $t=0$ the shape of the pulse is given by the function

$$D=\frac{4.0 \mathrm{~m}^3}{x^2+2.0 \mathrm{~m}^2} .$$

where $D$ and $x$ are in meters. Plot $D(x, t)$ vs, $x$ at $t=1.00 \mathrm{~s}$.

One of the most famous mathematical theorems of all time is called Fermat's Last Theorem. For more than $350$ years, the proof eluded mathematicians; it was finally cracked by Andrew Wiles in the $1990$s. Through Web research, learn what the theorem claims and why it became so famous. Briefly summarize how inductive evidence suggested its truth for centuries before Wiles finally found a deductive proof.

What is $electromagnetic$ $radiation$? Give some examples of such radiation. Explain what the $wavelength$ $(\lambda)$ and $frequency$ $(\nu)$ of electromagnetic radiation represent. Sketch a representation of a wave and indicate on your drawing one wavelength of the wave. At what speed does electromagnetic radiation move through space? How is this speed related to $\lambda$ and $\nu$?

Compare and contrast the bickering between characters in the play with similar interactions you have witnessed between people in real life. How is it similar? How is it different?

In each of the following situations, a wave passes through an opening in an absorbing wall. Rank the situations in order from the one in which the wave is best described by the ray approximation to the one in which the wave coming through the opening spreads out most nearly equally in all directions in the hemisphere beyond the wall.
(a) The sound of a low whistle at $1 \mathrm{kHz}$ passes through a doorway $1 \mathrm{~m}$ wide.
(b) Red light passes through the pupil of your eye.
(c) Blue light passes through the pupil of your eye.
(d) The wave broadcast by an AM radio station passes through a doorway $1 \mathrm{~m}$ wide.
(e) An x-ray passes through the space between bones in your elbow joint.

What happens to an electromagnetic wave as it passes from space to matter?

A. It changes frequency.

B. It changes wavelength.

C. It slows down.

D. It speeds up.

A loudspeaker produces sound waves that change in wavelength from 1.0 m to 1.5 m. If the wave speed is constant, how did the vibration of the loudspeaker change? Explain.

The current through a $20 \Omega$ inductive reactance is given. What is the sinusoidal expression for the voltage? Sketch the $v$ and $i$ sinusoidal waveforms on the same axis. a. $i=5 \sin \omega t$ b. $i=40 \times 10^{-3} \sin \left(\omega t+60^{\circ}\right)$ c. $i=-6 \sin \left(\omega t-30^{\circ}\right)$ d. $i=3 \cos \left(\omega t+10^{\circ}\right)$

(a) Analyze: What question does Ross ask that indicates he doubts that the grooms committed the murder? Explain.
(b) Infer: ls Ross satisfied by the answer? Explain.

a mole of photons of this radiation?

Approximately how long does it take a light wave to travel from your head to your toes? Assume you are standing straight up.