The diagram below represents a block sliding across a table at a constant speed. All forces are shown except the frictional force. What is the magnitude of the
frictional force on the block?
2.5 N
1.7 N
2.5 N

(a) assume the equation x = at^3 + bt describes the motion of a particular object, with x having the dimension of length and t having the dimension of time. determine the dimensions of the constants a and b. (use the following as necessary: l and t, where l is the unit of length and t is the unit of time.) (b) determine the dimensions of the derivative dx/dt = 3at^2 + b. (use the following as necessary: l and t, where l is the unit of length and t is the unit of time.)