The problem statement, all variables and given/known data The velocity of an object thrown vertically up in the air is given by V(t)=64-32t a) What is the average velocity during the first second? b) What is the average velocity between t=1 and t=3? The attempt at a solution a) displacement X1-X0 is given by the integral of v(t)dt between t=0 and t=1 solving integral gives 64t-16t^2. Entering time intevall between t=0 and t=1 give a displacement of 48m That is: average velocity is 48m/s the first second b) entering time bewteeen t=1 and t=3 gives dispplacement 192-144-(64-16)= 0 That is: average velocity is 0. This make sense since the curve x(t) is a parabole and t=2 give maximum height and velocity before that is positiv and after that is negative and so it cancels out Is this way of thinking correct?. I am a teacher (biology, not physics) and I am trying to help a friend with this problem. One more thing I am thinking about. The velocity equation is linear here. Is this realistic when throwing a object up in the air? It seem strange that this is linear. Wouldn't velocity varies in such a scenario?