The elements in a column of the periodic table a. have similar properties.
b. are in the same period.
c. have very similar chemical symbols.
d. have the same atomic mass.

Aboxcar traveling at 12 m/s approaches a string of 5 identical boxcars sitting stationary on the track. the moving boxcar collides and links with the stationary cars and they all move off together along the track. what is the final speed of the cars immediately after the collision? (you may take the mass of each boxcar to be 18,537 kg.)

Aforklift raises a 1,020 n crate 3.50 m up to a shelf. how much work is done by the forklift on the crate? the forklift does j of work on the crate.

The coefficient of friction is a number that represents the resistance to sliding between two in contact with one another.