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Do Now. How much work is being done if you…. ... Use 10 N to carry a puppy 10 m? ... Use 30 N to push a cart 30 m? ... Use 5,000 N to drag a sack of cats 100 m?. Announcements. Parent lab night rescheduled. Force and Motion unit test next Friday!. Today. INM Power Power calculations
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Do Now How much work is being done if you…. ... Use 10 N to carry a puppy 10 m? ... Use 30 N to push a cart 30 m? ... Use 5,000 N to drag a sack of cats 100 m?
Announcements • Parent lab night rescheduled. • Force and Motion unit test next Friday!
Today • INM Power • Power calculations • Demonstration
Power • Power is the rate at which work is done. • Power = Work/ Time • The unit of power is the watt.
How much power is used when you... ... Do 40 J of work for 4 s? ... Do 35 J of work in 7 s? ... Do 100 J of work in 10 s?
Okay, now the tough ones. It takes you 10 s to push a 50 kg box with a force of 75 N a distance of 100 m. How much work did you do? How much power did you use? In 2 s, you lift a 1 kg mass 10 m. How much work did you do? How much power did you use?
Okay, now the toughest one. You need to carry 100 physical science text books to the book room which is 80 m away. Each book has a mass of 2 kg. Which of the following situations would involve the least amount of work and power? A: You carry them one book at a time. B: You carry 10 books at a time. C: You carry all 100 books in one trip.