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A 25.0-cm-long metal rod lies in the $xy$-plane and makes an angle of 36.9$^\circ$ with the positive $x$-axis and an angle of 53.1$^\circ$ with the positive $y$-axis. The rod is moving in the $+x$-direction with a speed of 6.80 m/s. The rod is in a uniform magnetic field $\overrightarrow{B} =$ (0.120 T)$\hat{\imath}$ - (0.220 T)$\hat{\jmath}$ - (0.0900 T)$\hat{k}$. (a) What is the magnitude of the emf induced in the rod? (b) Indicate in a sketch which end of the rod is at higher potential.

(I) What is the longest wavelength of light that will emitelectrons from a metal whose work function is 3.70 $\mathrm{cV}$ ?

Two spectators at a soccer game see, and a moment later hear, the ball being kicked on the playing field. The time delay for spectator $A$ is 0.23 s, and for spectator $B$ it is 0.12 s. Sight lines from the two spectators to the player kicking the ball meet at an angle of $90^{\circ} .$ How far are (a) spectator $A$ and $(b)$ spectator $B$ from theplayer? (c) How far are the spectators from each other?

When the door of the Chapel of the Mausoleum in Hamilton, Scotland, is slammed shut, the last echo heard by someone standing just inside the door reportedly comes 15 s later. Ifthat echo were due to a single reflection off a wall opposite thedoor, how far from the door is the wall? (b) If, instead, the wall is25.7 $\mathrm{m}$ away, how many reflections (back and forth) occur?

Earthquakes generate sound waves inside Earth. Unlike a gas, Earth can experience both transverse (S) and longitudinal (P) sound waves. Typically, the speed of S waves is about$4.5 \mathrm{km} / \mathrm{s},$ and that of $\mathrm{P}$ waves 8.0 $\mathrm{km} / \mathrm{s} .$ A seismograph records $\mathrm{P}$ and $\mathrm{S}$ waves from an earthquake. The first $\mathrm{P}$ waves arrive 3.0 $\mathrm{min}$ before the first $S$ waves. If the waves travel in a straight line, howfar away did the earthquake occur?

A stone is dropped into a well. The splash is heard 3.00 s later. What is the depth of the well?