Based on your knowledge of the gravitational force near the surface of the earth and on newton's second law, explain the sign and magnitude of the acceleration of the coin in the last question during the three portions of its motion.

on its way up ;

at the highest point ;

on the way down ;

a. 9.8 m/s2
b. 0 m/s2
c. -9.8 m/s2
d. none of the other choices are correct for this situation.

mistakes are ok

scientific laws are the result of testing theories and proving them to be facts.

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.

i don't understand. explain it clearly