1 / 34

Conservation of Momentum

Conservation of Momentum. Review. Yeah! I already know this. p: momentum m: mass v: velocity p = m v p tot = p A0 + p B0 = p A1 + p B1 p tot = m tot v 2  only if A & B stick together. Example. Steps to Solve a Problem. Draw a BEFORE (State 0) picture

kory
Télécharger la présentation

Conservation of Momentum

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. Conservation of Momentum

  2. Review Yeah! I already know this. p: momentum m: mass v: velocity p = m v ptot = pA0 + pB0 = pA1 + pB1 ptot = mtotv2 only if A & B stick together

  3. Example

  4. Steps to Solve a Problem • Draw a BEFORE (State 0) picture • Draw an AFTER (State 1) picture • Label everything • Find missing pieces • Find the total momentum • Solve for what you don’t know

  5. Before (0) + - • Make sure you include: • Before (0) • Arrows • + & -

  6. After (1) + - • Make sure you include: • After (1) • Arrows • + & -

  7. Label Everything Before (0) After (1) - +

  8. Label Everything Before (0) After (1) A B A B - + Label each object A or B For every object include: m, v, p Use subscripts to label m, v, and p with A or B Use subscripts to label v, and p with 1 or 2

  9. Label Everything Before (0) After (1) A B A B - + m = v = p = m = v = p = m = v = p = m = v = p = Label each object A or B For every object include: m, v, p Use subscripts to label m, v, and p with A or B Use subscripts to label v, and p with 1 or 2

  10. Label Everything Before (0) After (1) A B A B - + mA = vA = pA = mB = vB = pB = mA = vA = pA = mB = vB = pB = Label each object A or B For every object include: m, v, p Use subscripts to label m, v, and p with A or B Use subscripts to label v, and p with 0 or 1

  11. Label Everything Before (0) After (1) A B A B - + mA = vA0 = pA0 = mB = vB0 = pB0 = mA = vA1 = pA1 = mB = vB1 = pB1 = Label each object A or B For every object include: m, v, p Use subscripts to label m, v, and p with A or B Use subscripts to label v, and p with 0 or 1

  12. Label Everything Before (0) After (1) A B A B - + mA = vA0 = pA0 = mB = vB0 = pB0 = mA = vA1 = pA1 = mB = vB1 = pB1 = Fill in all the numbers from the problem:

  13. Label Everything Before (0) After (1) A B A B - + mA = vA0 = pA0 = mB = vB0 = pB0 = mA = vA1 = pA1 = mB = vB1 = pB1 = Fill in all the numbers from the problem: A 3100 kg red roadster moving at 52 m/s has a head on collision with a 8300 kg green jeep moving at -34 m/s. The roadster bounces off with a velocity of -45 m/s. What is the final velocity of the jeep?

  14. Label Everything Before (0) After (1) A B A B - + mA = vA0 = pA0 = mB = vB0 = pB0 = mA = vA1 = pA1 = mB = vB1 = pB1 = Fill in all the numbers from the problem: A 3100 kg red roadster moving at 52 m/s has a head on collision with a 8300 kg green jeep moving at -34 m/s. The roadster bounces off with a velocity of -45 m/s. What is the final velocity of the jeep?

  15. Label Everything Before (0) After (1) A B A B - + mA = vA0 = pA0 = mB = vB0 = pB0 = mA = vA1 = pA1 = mB = vB1 = pB1 = Use units to help you figure it out (kg = m, m/s = v, kgm/s = p): A 3100 kg red roadster moving at 52 m/s has a head on collision with a 8300 kg green jeep moving at -34 m/s. The roadster bounces off with a velocity of -45 m/s. What is the final velocity of the jeep?

  16. Label Everything Before (0) After (1) A B A B - + mA = 3100 kg vA0 = 52 m/s pA0 = mB = 8300 kg vB0 = -34 m/s pB0 = mA = 3100 kg vA1 = -45 m/s pA1 = mB = 8300 kg vB1 = pB1 = Use units to help you figure it out (kg = m, m/s = v, kgm/s = p): A 3100 kg red roadster moving at 52 m/s has a head on collision with a 8300 kg green jeep moving at -34 m/s. The roadster bounces off with a velocity of -45 m/s. What is the final velocity of the jeep?

  17. Label Everything Before (0) After (1) A B A B - + mA = 3100 kg vA0 = 52 m/s pA0 = ? mB = 8300 kg vB0 = -34 m/s pB0 = ? mA = 3100 kg vA1 = -45 m/s pA1 = ? mB = 8300 kg vB1 = ? pB1 = ? Fill in what you don’t know with question marks: A 3100 kg red roadster moving at 52 m/s has a head on collision with a 8300 kg green jeep moving at -34 m/s. The roadster bounces off with a velocity of -45 m/s. What is the final velocity of the jeep?

  18. Find Missing Pieces Before (0) After (1) A B A B - + mA = 3100 kg vA0 = 52 m/s pA0 = ? mB = 8300 kg vB0 = -34 m/s pB0 = ? mA = 3100 kg vA1 = -45 m/s pA1 = ? mB = 8300 kg vB1 = ? pB1 = ? If you know 2 out of 3 (m, v, p) you can find what’s missing.

  19. Find Missing Pieces Before (0) After (1) A B A B - + mA = 3100 kg vA0 = 52 m/s pA0 = ? mB = 8300 kg vB0 = -34 m/s pB0 = ? mA = 3100 kg vA1 = -45 m/s pA2 = ? mB = 8300 kg vB1 = ? pB1 = ? If you know 2 out of 3 (m, v, p) you can find what’s missing.

  20. Find Missing Pieces Before (0) After (1) A B A B - + mA = 3100 kg vA0 = 52 m/s pA0 = 161200 mB = 8300 kg vB0 = -34 m/s pB0 = -282200 mA = 3100 kg vA1 = -45 m/s pA1 = -139500 mB = 8300 kg vB1 = ? pB1 = ? If you know 2 out of 3 (m, v, p) you can find what’s missing. Use: p = mv

  21. Find Total Momentum Before (0) After (1) A B A B - + mA = 3100 kg vA0 = 52 m/s pA0 =161200 mB = 8300 kg vB0 = -34 m/s pB0 =-282200 mA = 3100 kg vA1 = -45 m/s pA1 =-139500 mB = 8300 kg vB1 = ? pB1 = ? ptot = pA0 + pB0 & ptot = pA1 + pB1

  22. Find Total Momentum Before (0) After (1) A B A B - + mA = 3100 kg vA0 = 52 m/s pA0 =161200 mB = 8300 kg vB0 = -34 m/s pB0 =-282200 mA = 3100 kg vA1 = -45 m/s pA1 =-139500 mB = 8300 kg vB1 = ? pB1 = ? ptot = pA0 + pB0 & ptot = pA1 + pB1 Use what you know: ptot = 161200 -282200 = -121000

  23. Find the Missing Momentum Before (0) After (1) A B A B - + mA = 3100 kg vA0 = 52 m/s pA0 =161200 mB = 8300 kg vB0 = -34 m/s pB0 =-282200 mA = 3100 kg vA1 = -45 m/s pA1 =-139500 mB = 8300 kg vB1 = ? pB1 = ? Use what you know and a little algebra: ptot = pA0 + pB0 & ptot = pA1 + pB1 ptot = -121000

  24. Find the Missing Momentum Before (0) After (1) A B A B - + mA = 3100 kg vA0 = 52 m/s pA0 =161200 mB = 8300 kg vB0 = -34 m/s pB0 =-282200 mA = 3100 kg vA1 = -45 m/s pA1 =-139500 mB = 8300 kg vB1 = ? pB1 = ? Use what you know and a little algebra: ptot = pA1 + pB1

  25. Find the Missing Momentum Before (0) After (1) A B A B - + mA = 3100 kg vA0 = 52 m/s pA0 =161200 mB = 8300 kg vB0 = -34 m/s pB0 =-282200 mA = 3100 kg vA1 = -45 m/s pA1 =-139500 mB = 8300 kg vB1 = ? pB1 = ? Use what you know and a little algebra: ptot = pA1 + pB1 -pA1 -pA1

  26. Find the Missing Momentum Before (0) After (1) A B A B - + mA = 3100 kg vA0 = 52 m/s pA0 =161200 mB = 8300 kg vB0 = -34 m/s pB0 =-282200 mA = 3100 kg vA1 = -45 m/s pA1 =-139500 mB = 8300 kg vB1 = ? pB1 = ? Use what you know and a little algebra: ptot = pA1 + pB1 -pA1 -pA1 pB1 = ptot – pA1

  27. Find the Missing Momentum Before (0) After (1) A B A B - + mA = 3100 kg vA0 = 52 m/s pA0 =161200 mB = 8300 kg vB0 = -34 m/s pB0 =-282200 mA = 3100 kg vA1 = -45 m/s pA1 =-139500 mB = 8300 kg vB1 = ? pB1 = ? Use what you know and a little algebra: pB1 = ptot – pA1 = -121000 - (-139500) = 18500

  28. Solve for What You Don’t Know Before (0) After (1) A B A B - + mA = 3100 kg vA0 = 52 m/s pA0 =161200 mB = 8300 kg vB0 = -34 m/s pB0 =-282200 mA = 3100 kg vA1 = -45 m/s pA1 =-139500 mB = 8300 kg vB1 = ? pB1 = 18500 Use p = mv and a little algebra:

  29. Solve for What You Don’t Know Before (0) After (1) A B A B - + mA = 3100 kg vA0 = 52 m/s pA0 =161200 mB = 8300 kg vB0 = -34 m/s pB0 =-282200 mA = 3100 kg vA1 = -45 m/s pA1 =-139500 mB = 8300 kg vB1 = ? pB1 = 18500 Use p = mv and a little algebra: pB1 = mBvB1

  30. Solve for What You Don’t Know Before (0) After (1) A B A B - + mA = 3100 kg vA0 = 52 m/s pA0 =161200 mB = 8300 kg vB0 = -34 m/s pB0 =-282200 mA = 3100 kg vA1 = -45 m/s pA1 =-139500 mB = 8300 kg vB1 = ? pB1 = 18500 Use p = mv and a little algebra: pB1 = mBvB1 mB mB .

  31. Solve for What You Don’t Know Before (0) After (1) A B A B - + mA = 3100 kg vA0 = 52 m/s pA0 =161200 mB = 8300 kg vB0 = -34 m/s pB0 =-282200 mA = 3100 kg vA1 = -45 m/s pA1 =-139500 mB = 8300 kg vB1 = ? pB1 = 18500 pB1 = mBvB1 mB mB . vB1 = pB1 mB

  32. Solve for What You Don’t Know Before (0) After (1) A B A B - + mA = 3100 kg vA0 = 52 m/s pA0 =161200 mB = 8300 kg vB0 = -34 m/s pB0 =-282200 mA = 3100 kg vA1 = -45 m/s pA1 =-139500 mB = 8300 kg vB1 = ? pB1 = 18500 vB1 = pB1 = 18500 mB 8300 kg vB1 = 2.2 m/s

  33. Celebrate!You Did It! J. Gabrielse

  34. Classwork • p. 210: 11 & 12

More Related