Two boxes are arranged so one is on a table and then it is connected to a second by a rope that passes over a pulley and it attached to the second box. The second box is not in contact with any surface. Box A has a mass of 90.0kg and Box B has a mass of 50.0kg. There is a coefficient of friction between Box A and the table that is 0.350. Calculate the normal force on Box A
Calculate the friction force of Box A
Calculate the tension on the rope
Calculate the acceleration of the systems

This should help

Explanation: http:

//www.physics.gsu.edu/dhamala/Phys1111/chap5.pdf

http://bedfordjfhs.sharpschool.net/common/pages/DisplayFile.aspx?itemId=20872174

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.