A RED toy car of mass 4.7 kg, hits BLUE toy car, with mass 1.2 kg, head-on. The blue car originally had a velocity of -15 m/s. After the two cars collide, they stick together and stop. What was the Red car's original velocity?

what experimental evidence led scientists to change from the previous model to this one?

a few of the positive particles aimed at a gold foil seemed to bounce back.

the colors of light emitted from heated atoms had very specific energies.

experiments with water vapor showed that elements combine in specific proportions.

cathode rays were bent in the same way whenever a magnet was brought near them.

the answer is 12 as i may remember

: )