Every object in existence has mass. Mass is a measurement of the amount of matter than an object has. Weight and mass, however, are not the same thing. Weight is calculated by multiplying an object's mass and its acceleration due to gravity. W = m × g Why is the weight of an object different from planet to planet? A. The mass of an object changes when it is on different planets. B. This statement is not true; objects have the same weight from planet to planet. C. The acceleration due to gravity varies from planet to planet. D. The amount of air varies from planet to planet.

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