If a pole vaulter jumps 7.6 m and his potential energy is 5000 J at the midpoint of his jump, what is his mass?

You have been called to testify as an expert witness in a trial involving a head-on collision. car a weighs 1515 lb and was traveling eastward. car b weighs 1125 lb and was traveling westward at 44.0 mph. the cars locked bumpers and slid eastward with their wheels locked for 22.5 ft before stopping. you have measured the coefficient of kinetic friction between the tires and the pavement to be 0.750 . how fast (in miles per hour) was car a traveling just before the collision? (this problem uses english units because they would be used in a u.s. legal proceeding.)

Which atomic model was proposed as a result of j. j. thomson’s work?

What is the increase in density of a medium due to wave travel?