A car of mass 1000 kg is heading east at 25 m/s. It collides with a car of mass 1200 kg heading north at 30 m/s. When the cars collide, they stick together. a. What is the total momentum of the system before the collision? Remember that momentum is a vector quantity, and write the momentum in component notation, with x and y unit vectors. (1 point)
b. What is the total momentum of the system after the collision? Write the momentum in component notation, with x and y unit vectors. (1 point)
c. What is the velocity of the cars after the collision? Write the velocity in component notation, with x and y unit vectors. (1 point)
d. At what angle do the cars move after the collision? (1 point)

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