PHYSICS · Subjective · A Level · Physics · Measurements and their errors · Measurements and their errors
Problem
Consider the expression
P=AF+ρv2,
where P is pressure, F is force, A is area, ρ is density of the fluid and v is the speed of flow.
(a) Test whether the expression is dimensionally homogeneous.
(b) If the expression is not dimensionally correct, modify only the second term with the smallest possible change so that the equation becomes dimensionally consistent.
(c) For water of density 1000kg/m3 flowing with speed 4m/s, calculate the numerical value (in pascal) of the corrected second term obtained in part (b).