1 / 17

Motion

Motion. Motion is a change in an object’s position relative to a reference point. Definition. Motion is Relative. Relative – it is described compared to a REFERENCE POINT Example: As a car drives away from school its position is changing relative to school. Describing motion .

wentworth-bruno
Download Presentation

Motion

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. Motion

  2. Motion is a change in an object’s position relative to a reference point. Definition

  3. Motion is Relative • Relative – it is described compared to a REFERENCE POINT • Example: As a car drives away from school its position is changing relative to school.

  4. Describing motion • We describe motion in words, with graphs and using mathematical quantities. • The mathematical quantities we use to describe motion are distance, time, speed, velocity and acceleration.

  5. Describing motion • These mathematical quantities have certain SI units.

  6. Speed: We are concerned with 3 different types of speed. • Speed is the rate of change in position. • We will talk about average speed, instantaneous speed, and constant speed.

  7. Speed: Average Speed • Total distance traveled divided by the time interval during which the motion occurred. • s= d / t • t = d / s • d = s x t Example: If you travel 200 miles In 4 hours, your average speed is 50 mph.

  8. SpeedInstantaneous Speed • Speed at any instant Example: In your trip, you might be going 60 mph one moment and Slowing down and stopping for a break a few moments later.

  9. SpeedConstant Speed • Speed that does not change • Instantaneous speed that does not change • When an object has a constant speed, its average speed and instantaneous speed will be the same.

  10. Velocity • Speed AND direction • This is important for a full description of motion • Pilots need to know wind speed and direction. • Calculations of velocity are different than speed. • v= change in position / time

  11. Velocity: Direction matters • Imagine that two birds leave the nest at the same time. The both fly at 10 km/h for 5 min, 12 km/h for 8 min, and 5 km/h for 10 min. Why don’t they end up at the same place?

  12. A swimmer swims 50 m in 40 s. What is the swimmer’s average speed? Problem

  13. A swimmer swims 20 m in 40 s. What is the swimmer’s average speed? S = D/T S = 50m/40s S = 1.25m/s

  14. What is the average speed (mph) for a car journey of 120 miles that began at 09:30am and finished at 12:00 noon? Problem

  15. What is the average speed (mph) for a car journey of 120 miles that began at 09:30 and finished at 12:00 noon? S = D/T D = 120 T = 2.5 hours (from 9:30 – 12:00) S = 120m / 2.5h S = 48 mph Problem

  16. How far does a bicycle travel at a speed of 6 m/s for 15 seconds?

  17. How far does a bicycle travel at a speed of 6 m/s for 15 seconds? s=d/t 6m/s = d/15s 15s (6m/s) = d/15s (15s) 90 m = d

More Related