Test #2 Review Sheet - Introduction to Physics Survey | PHYS 1030, Exams of Physics

Download Test #2 Review Sheet - Introduction to Physics Survey | PHYS 1030 and more Exams Physics in PDF only on Docsity! Review for test number 2. Know the definitions of the different types of energies. Give examples of renewable and non-renewable resources and fossil fuels. Work = force X displacement. Pull a cart with a force of 120 N for a displacement of 5 m. The work is 120N x 5m = 600 Joules If there is no displacement there is no work. Also if the force and the displacement are perpendicular to each other there is no work. kinetic energy = ½ m v2 work = change in kinetic energy 1 horsepower = 746 Watts. multiply the number of horsepower by 746 to get the number of Watts. example: 50 hp = 37300 Watts Power = Work/time example: it takes 6 seconds for a 10 Watt motor to do 60 Joules of work. Find the power by dividing the work by the time. Power = (200000 J)/(6 s) = 33333 Watts also power = change in kinetic energy / time example: 1000kg car speeds up from 0 m/s to 20 m/s in a time of 6 seconds. The change in kinetic energy is: ½ (1000 kg)(20 m/s)2 - ½ (1000 kg)(0m/s)2 = 200000 J Power = (200000 J)/(6 s) = 33333 Watts Power can also be described as Force x velocity Power = Force x velocity Apply a 60 N force while moving a box 5 m/s. The power is (60N)x(5 m/s)= 300 Watts gravitational potential energy = mass x gravity x height. Lower a 50 kg block a distance of 2 meters. You lowered the gravitational energy by: (50 kg) x (9.8 m/s2) x (2 m) = 980 Joules When converting potential energy to kinetic energy set up the following equation: m g h = ½ m v2 Notice that the mass cancels out; this gives: ghv 2