1. Not sure if it's the right forum but I'll try. The velocity of an particle varies quadratic with a formula based on time a) Find the equation for acceleration and length as a function of time. b) a = 3 m/s^3 (I think it's alpha) Find the acceleration when t1=2s t2=5s and how big is the mean acceleration in the time intervall t2-t1. 2. See picture 3. a) I think you can use the formula saying u=0 (start velocity) and say a=(v-u)/t And do the same for where s= length. But is it that easy or are they looking for a different solution, as this is something I learned few years ago. Or do I have to antiderivate it, which would make it complicated because there is no known fact. b) If a) is right could I then say solve v(t) which gives me t=3 alpha= 3 --> v(t)=27 m/s, and then get acceleration by the 2nd formula v= 27 u=0 t=3, so acceleration is 9? Or am I on the wrong way?