Successfully reported this slideshow.
We use your LinkedIn profile and activity data to personalize ads and to show you more relevant ads. You can change your ad preferences anytime.

Scalars And Vectors


Published on

Published in: Education
  • Be the first to like this

Scalars And Vectors

  1. 1. Scalars and VectorsScalars and Vectors By: Lee Yi LiangBy: Lee Yi Liang Joshua Foo and Ryan WongJoshua Foo and Ryan Wong
  2. 2. What is scalar? • Scalar quantities only takes into account the magnitude of a measurement, but not its direction. This is where it differs from vector quantities.
  3. 3. Examples of scalar quantities • Speed: 100km/h; Vector would be velocity: 100km/h heading north • Temperature: 30o C • Time: 10s
  4. 4. Vectors • Quantities with magnitude and direction • Have positive and negative quantities
  5. 5. Vectors • All vectors can be broken up into 4 parts – North – South – East – West • Magnitudes of vectors can be compared – |A| compared to |B|
  6. 6. Vectors • Example: – Displacement – Velocity – Acceleration – Force – Electric field
  7. 7. How to represent a vector?How to represent a vector?
  8. 8. How? Like This! • Scaled vector diagrams • Depict a vector by use of an arrow drawn to scale in a specific direction
  9. 9. Huh but how? • All vector diagrams should contain the following: – Clearly listed scale – Vector arrow in specified direction – Vector arrow must have • a head • a tail – Cleary labeled magnitude and direction of vector – In this case, magnitude is 20m and direction is 30 degrees west of north
  10. 10. • Ohh like that ar?
  11. 11. SOLVING RESULTANT OF 2 VECTORS Geometrically
  12. 12. Things to note • Dot represents the object • Arrows represent the forces. • Length of arrows represent magnitude of forces. • Direction arrows are pointing to represent direction of forces.
  13. 13. Scenario • Let’s say, there are two forces acting on an object. One force is acting 100N upwards, the other is 50N to the right.
  14. 14. Step 1 – Drawing object and forces . 100N 50N
  15. 15. Step 2 – Move one arrow along the other . 100N 50N OR . 100N 50N
  16. 16. Step 3 – Draw an arrow from object to point where the moved arrow is touching . 100N 50N OR . 100N 50N
  17. 17. Step 4 – Measure length of resultant arrow • After you find out the length of the arrow, find out the ratio of the resultant arrow to the ratio of any of the beginning arrows. • Hence deduce the force.
  18. 18. How to determine theHow to determine the resultant of 2 vectorsresultant of 2 vectors mathematically?mathematically?
  19. 19. But then but then but then hor • In the diagram, R is the resultant displacement of displacement vectors A, B, and C • A + B + C = R • In all such cases, the resultant vector is the result of adding the individual vectors
  20. 20. But then but then but then still got more • Pythagoras Theorem – Can be used to determine the result of adding two (and only two) vectors which make a right angle to each other
  21. 21. But then never mind • Trigonometry – Can be used to determine direction of resultant vector
  22. 22. Result of more vectors • Forces in a Plane • Forces in 90 degrees • Forces in all directions
  23. 23. Result of more vectors • Forces in Plane – Simply add all the forces together
  24. 24. Result of more vectors • Forces in 90 degrees – Add up the vector forces in north and south – Add up the vector forces in east and west – Make a right angle triangle – Use trigonometry to find resultant force
  25. 25. Result of more vectors • Addition of Vector – Represent the vector forces with arrows • Greater magnitude, longer arrow – Place all the arrows at the same starting point – Choose an arrow – Choose the next arrow • At the end of the 1st arrow, place the start of the 2nd arrow
  26. 26. Result of more vectors – Continue until all the arrows are joint together – All the arrows should end at a point • Match this ending point to the starting point – This new arrow is the resultant force
  27. 27. Acknowledgements • The Physics Classroom - The Electronic Science Tutor - Resultant of Forces -
  28. 28. The End • Qs?