Vertical Circular Motion

1
Vertical Circular Motion

• 5.7

2
Loop-the-Loop

• As the car or motorcycle goes around loop
• The centripetal force can be found in four places
  easily

3
Loop-the-Loop

• FN1-mgmv2/r
• FN2 mv2/r
• FN3mgmv2/r
• FN4 mv2/r

4
Loop-the-Loop (top)

• Must have minimum speed at top of loop
• FN3mgmv2/r
• FN3 0 if barely touching
• mgmv2/r ? g v2/r

5
Loop-the-Loop (top)

• If FN 0 at top of Loop
• No force from the track
• Centripetal force provided by weight
• Rider experiences apparent weightlessness

6
Example

• A 10-gram Hot Wheels car goes around a vertical
  loop with radius 5 cm. What speed must it have
  at the top of the track to maintain contact?
• v 0.70 m/s
• What Force does it undergo at the bottom of the
  loop if it has a speed of 5 m/s?
• F 4.9 N

7
Practice Problem

• Dont let these problems throw you for a loop!
• 142CQ14 - 16, P36 40
• Total of 8 problems