Work and Power

Master work & power calculations!

USE YOUR NOTES FROM CLASS TO ANSWER THE QUESTIONS.USE YOUR DESMOS CALCULATOR WHEN NECESSARY.Be sure to use your _ Notes Work is done when an object moves moves in the direction of the force stays in place The formula for work is Work = force x distance Work = force + distance Work = force - distance The SI unit for work is Newtons (N) Meters (M) Joules (J) Power is the amount of work done over a period of time OR how fast work is done how strong you are when you move an object in the direction of a force The formula for power is Power = Work x Time Power = Work / Time Power = Work + Time The SI unit for power is Joule (J) Newton (N) Watt (W) Classify the situation as WORK or NO WORK.Craig is pushing a 100 pound weight across the floor. Work No work Classify the situation as WORK or NO WORK.Carlos is sitting at his desk. Work No work Classify the situation as WORK or NO WORK.Betty is thinking about her science test. Work No work Classify the situation as WORK or NO WORK.Nancy lifts her backpack from the floor when she leaves to go to the next class. Work No work Classify the situation as WORK or NO WORK.Bob was standing in line at the store while holding a 2 liter bottle of Dr. Pepper, a Slim Jim, a bag of pretzels, a bag of gummy bears, and a Snickers. Work No work Classify the situation as WORK or NO WORK.A bulldozer is pushing dirt across the field. Work No work Classify the situation as WORK or NO WORK.Trey handed his friend 2 pencils and a pen. Work No Work Classify the situation as WORK or NO WORK.Barbara was waiting at the classroom door with her backpack, soccer bag, lunch bag, and her Chromebook in her hands. Work No Work If a 400 N runner races 50 meters, how much work was done?W = f x d 8 J 20,000 J 80 N A machine does 280 J of work in 4 seconds? What is the power?P = w ⁄ t 7 W 70 W 1120 J A student who weighs 600 Newtons climbed the stairs from the 1st floor to the 2nd floor, 15 meters up.How much work did he do? W = f x d 40 N 9,000 J 40 J A student who weighs 600 Newtons climbed the stairs from the 1st floor to the 2nd floor, 15 meters up in 20 seconds.What is his power? P = W ⁄THint: Find the work first or look at the last question. 450 W 45 W 135,000 W Lisa pushes a 150 N cart down the hall 20 meters. How much work was done?W = f x d 7.5 J 75 N 3000 J Lisa pushes a 150 N cart down the hall 20 meters in 30 seconds. What was her power?P = w ⁄ tHint: Find work first or look at the last question. 100 W 1000 N 3000 W A 500 N passenger is inside an elevator that rises 30 meters. How much work was done on the elevator trip?W = f x d 15,000 J 16.7 J 1,500 W A 500 N passenger is inside an elevator that rises 30 m in exactly 25 seconds. How much power is needed for the elevator trip?P = w ⁄ tHint: Find work first or look at the last question. 15,000 J 600 W 15,000 W If a hair dryer uses 350 J of energy in 10 seconds, what was the power used?P = Energy ⁄ time 3500 W 35 W 350 J A teacher carries her 90 N backpack and 10 N lunch box 30 meters down the hall. How much work is done? Be careful on this one!W = f x d 0 J 2,700 J 3000 J 900 J