An ambulance with its siren on drives towards you. What happens to the wavelength of the sound you hear?
[Wavelegnth decreases]

Moon effect. some people believe that the moon controls their activities. if the moon moves from being directly on the opposite side of earth from you to being directly overhead, by what percentage does (a) the moon's gravitational pull on you increase and (b) your weight (as measured on a scale) decrease? assume that the earth–moon (center-to-center) distance is 3.82 × 10^8 m, earth's radius is 6.37 × 10^6 m, moon's mass is 7.36 × 10^22 kg, and earth's mass is 5.98 × 10^24 kg.

The free body diagram shows a box being pulled to the left up a 25-degree incline. the magnitude of the normal force is

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