a sled with mass 8.00 kg moves in a straight line on a frictionless horizontal surface. at one point in its path, its speed is 4.00 m/s; after it has traveled 2.50 m beyond this point, its speed is 6.00 m/s. use the work-energy theorem to find the force acting on the sled, assuming that this force is constant and that it acts in the direction of the sled’s motion.

Of the 168 hours in a week as a full time student you should spend how many hours per week on school work?

Two technicians are discussing how to test a car's exhaust by holding a small piece of paper within an inch of the tailpipe mouth. technician a says that if the paper is vibrating due to a "puffing" output from the tailpipe, this signals a smoothly running engine. technician b says that if the paper is being drawn toward the tailpipe, this could indicate burned exhaust valves. who is correct? a. technician b b. both technicians a and b c. technician a d. neither technicians a or b

Which statements about the two fossil images are correct? 1. cave bears are ancestors of plateosaurus. 2. plateosaurus were present on earth before ostracoderms. 3. ostracoderms were the first to die. 4. plateosaurus died after the ostracoderms. 5. cave bears are the oldest fossils.