# part

A 3.49 kg ball is dropped from the roof of a building 187.2 m high. While the ball is falling to Earth, a horizontal wind exerts a constant force of 13.2 N on the ball. How long does it take to hit the ground? The acceleration of gravity is 9.81 m/s How far from the building does the ball...
2. ### ____What is What is Not Part 2_________

Best to read the first part but basically we deduced that in 2018 there is not a correct definition of Up or Down that fits current science. Frankly it is below bad when science cannot even define Up and Down when? Answer this: Why should I believe science when it cannot even define Up...
3. ### Deriving equations (3 part question!)

I need help with all the following and will post under each what I believe the answer is. Thank you in advance! A body of mass m accelerates uniformly from rest to a speed of V in total time T. (a) Mathematically derive an equation for the work done on the body as a function of time T. W=...
4. ### I need help with the final part of a long momentum problem

This question has 4 parts. I managed to do a) to c) but I can't figure out d) at all. A student is throwing bricks at his physics teacher. The bricks have a mass of 2 kg and the student can throw them with a speed of 10 m/s. The teacher is standing on a frozen lake so there is no friction and...
5. ### Perturbation approach to solve attractive part of Lennard-Jones potential

The text is taken from this site: http://www.chem.konan-u.ac.jp/PCSI/web_material/LJ.pdf I don't get the definition added just after (7). Where is it taken from and what does it mean? Why is it the energy? And can someone show the arithmetics and the fundamental principles on how to get from...