1 / 11

P H Y S I C S Chapter 4: Work and Energy Section 4F: Power

P H Y S I C S Chapter 4: Work and Energy Section 4F: Power. Power. The rate at which work is done. Work vs. Power. Student A Student B. Work vs. Power. Power accounts for “how fast” work is done. A. B. Power Equation. Unit: P  power (W) W  work (J) t  time (s).

ghazi
Download Presentation

P H Y S I C S Chapter 4: Work and Energy Section 4F: Power

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. P H Y S I C S Chapter 4: Work and Energy Section 4F: Power

  2. Power • The rate at which work is done

  3. Work vs. Power • Student A • Student B

  4. Work vs. Power • Power accounts for “how fast” work is done A B

  5. Power Equation Unit: • P  power (W) • W  work (J) • t  time (s)

  6. Power Equation • Another variation derived from : • P  power (W) • F  force (N) • v  velocity (m/s)

  7. Household Appliances • 60W light bulb - 60W • Toaster : 800-1500W • Microwave : 600-1500W • Dishwasher : 1200-1500W • Washing Machine : 500W • Vacuum Cleaner : 200-700W • Clothes dryer : 4000W • Ceiling Fan : 10-50W • Hair Blow dryer : 1000W • Laptop Computer : 20-50W • Desktop Computer : 80-150W • Cell Phone Charger: 3-5W • iPod/iPad Charger: 10W

  8. Horsepower • 1 horsepower (hp) = 746 Watts

  9. In-Class Problem #1 What force would a 300 hp engine have to produce to keep a vehicle at a steady 23 m/s against air resistance and friction? F = 9,730 N Air Resistance Engine Force Friction

  10. In-Class Problem #2 A 300 kg crate needs to be hoisted to a height of 20 m. How long will a 1500 W crane motor take to do this? t = 40 s

  11. Assignment • Problem Set 4F • 4E-4F Quiz (Non-Conservative Forces and Power)

More Related