La velocità massima permessa in alcune aree dei centri urbani è di 30 km/h invece di 50 km/h . Esprimi questi valori in metri al secondo. A quante aule lunghe 7 m corrispondono, approssimativa mente, le distanze percorse a queste velocità in 1 s? Quale limite sceglieresti per le aree urbane vicino alle scuole? Giustifica la tua scelta .

Which of these is not a possible type of energy transformation? a. electrical energy into light energy b. sound energy into nuclear energy c. potential energy into kinetic energy d. kinetic energy into mechanical energy

What happens when you slowly pulled the carboard?

1. what is the relationship between wavelength and the penetrating power of an electromagnetic wave? a) the penetrating power has no relationship to the wavelength. b) the penetrating power increases as the wavelength increases. c) the penetrating power decreases as the wavelength increases. d) the penetrating power decreases as the wavelength decreases. 2. as ice melts and turns into water, the speed of sound through the material would most likely do what? justify your answer. a) the speed would not change because the material is always water. b) the speed of sound would increase because the density of water is less than that of ice. c) the speed of sound would increase because energy is added to ice in order to make it melt. d) the speed of sound would decrease because sound travels faster through solids than liquids. 3.which of these waves need a medium to travel through? a) sound b) x-rays c) infrared rays d) visible light