27. A bicycle wheel on a repair bench can be accelerated either by pulling on the chain that
is on the gear or by pulling on a string wrapped
around the tire. The tire's radius is 0.38 m, while
the radius of the gear is 0.14 m. What force would
you need to pull on the string to produce the
same acceleration you obtained with a force of
15 N on the chain?

the diagram which shows forces as either balanced = same speed or unbalanced = accelerarting

f=ma a/f/m a= 480/60 a = 8m/s/s that is quick wow

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.