A person pulls hori- zontally on block B in Fig. E4.28, causing both blocks to move together as a unit. While this system is moving, make a carefully labeled free-body dia- gram of block A if (a) the...

A person pulls hori-

zontally on block B in Fig.

E4.28, causing both blocks to

move together as a unit. While

this system is moving, make a

carefully labeled free-body dia-

gram of block A if (a) the table

is frictionless and (b) there is friction between block B and the

table and the pull is equal to the friction force on block B due to

the table.