Show that the function ψ(z, t) = (z + vt) 2 is a nontrivial solution of the differential wave equation. in what direction does it travel?

Molten iron fills a mould, which has a volume of 200 cm cubed. calculate the volume when the iron cools and solidifies.

Avery hard rubber ball (m = 0.5 kg) is falling vertically at 4 m/s just before it bounces on the floor. the ball rebounds back at essentially the same speed. if the collision with the floor lasts 0.05 s, what is the average force exerted by the floor on the ball?

Which statement is true? a. kepler's laws apply only to the motion of earth. b. kepler's laws can be used to predict eclipses. c. kepler's laws are true for a central force that is directly proportional to distance. d. kepler's laws can be deduced from newton's laws of motion and gravity.