Two masses m1 and m2 move in a plane and interact by a potential energy u(r) = 1/2kr^2. write down their lagrangian in terms of the cm and relative positions r and r, and find the equations of motion for the coordinates x, y and x, y. describe the motion and find the frequency of the relative motion.

Abaseball has a mass of 0.145 kg and approaches a bat at 40.0 m/s. after it is hit, the ball leaves the bat at 50.0 m/s directly back. find the impulse of the bat on the ball. 7.25 kg*m/s 13.1 kg*m/s 5.80 kg*m/s 1.45 kg*m/s

4. who was the first one to measure the speed of light and conclude that it is finite? 5. who was the first philosopher who thought the speed of light is finite? 13. what is the speed of light numerically? 14. give an example of something moving faster than light 15. give an example for some particles or waves that

Lymphocytes known as blastocysts make antibodies that fight infection. select the best answer from the choices provided t f