A train passes by an little boy at the depot. as is moves away from the boy at 65 m/s, the whistle emits a feaquency of 4500hz. what freaquency does the little boy hear as the train barrels off into the distance? speed of sound in air is 343 m/s

Write down two additional questions about earth's magnetic field that will make your presentation more informative.

The average density of the planet uranus is 1.27 103 kg/m3. the ratio of the mass of neptune to that of uranus is 1.19. the ratio of the radius of neptune to that of uranus is 0.969. find the average density of neptune.

Which of the following changes will increase the capacitance of a parallel-plate capacitor? (there could be more than one correct choice.) a) increase the charge on the plates b) decrease the poten5al between the plates c) increase the potential between the plates d) introduce a dielectric material between the plates e) decrease the separation between the plates