What makes simple machines useful for people without enough strength to
complete a task?
a) work is reduced, while time is decreased.
b) input force is reduced, while time is increased,
c) power is creased, while distance is decreased. d) input force is reduced, while distance is increased.

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.