Seven identical dominoes (i.., blocks) each of mass m=1kg are to be stacked in three columns and pushed across a frictionless ice rink by a horizontal 10-N force.Assume dominoes do not slip w.r.t. each other. How many dominoes should be in each column, with a minimum of one, (a) to maximize the acceleration of the dominoes, (b) to maximize the force on column C due to column B, (c ) to maximize the net force on column B due to column A and C, and (d) to maximize the force on column B due to column A?

Explanation

(a) Acceleration of dominoes does not depends upon the number of block as acceleration `a=(F)/("Total mass") =(10)/(7) ms^(-2)`
(b) The maximize force on column C due to column B. The mass of column-C should be maximum. But at least on block should be on one column. Hence 5 blocks should be on colume C and one each on column A and B.
(c) Similarly to maximize the force on cloumn B. Maximum mass should be on column B. Hence column A-one, column-B-five, and column C-one.
(d) To maximize force on column B due to column A only one block should be on column A and remaining six can be placed in any arrangement.