The forum discussion centers on the implications of mass change in a system as described by Newton's second law, particularly in the context of a wheelbarrow moving with water. Participants debate the validity of the equation $$F = \frac{d}{dt}(mv) = \frac{dm}{dt}v + m\frac{dv}{dt}$$, asserting that it misrepresents the relationship between force and mass change. The conversation highlights the importance of correctly defining forces in systems with variable mass and the need to adhere to Newtonian dynamics without conflating it with relativistic concepts.
PREREQUISITESPhysics students, educators, and anyone interested in the nuances of classical mechanics and the application of Newton's laws in variable-mass scenarios.
until the moment the element of mass enters the cart. After the addition this element of mass ##dm## will produce its effect on the way the whole system reponds to the constant force.A.T. said:In this particular case, with no relative velocity, no force is needed to accelerate the added mass to the velocity of the cart on addition.