Measure the max angle of a 3D pendulum

  • Thread starter cuallito
  • Start date
  • #1
81
1
Hi, I need a simple way to measure the maximum angle/vertical displacement of a 3D pendulum (weight hanging from a rope) undergoing random impacts. What will work?
 

Answers and Replies

  • #2
berkeman
Mentor
59,059
9,157
Whelp, you could buy a $50,000 3-D camera measurement system and software, or you could use your hand and a tape measure. What's your pleasure?
 
  • #3
Baluncore
Science Advisor
8,693
3,351
Let the rope pass through a hole in a table. Place a radial array of flat rulers on the table. They will be pushed away by the pendulum rope. Read the distance they are pushed, with y = height of fulcrum above the table, and x = maximum push of ruler, theta = Atan( x / y ).

See; https://en.wikipedia.org/wiki/Ballistic_pendulum
 
  • #4
255
30
You could use a common video camera. It won't be as accurate as a true high speed camera, but it should suffice for experimental purposes. Mount the camera in front of the pendulum at the height of the pendulum at rest. Put a screen behind the pendulum with a pattern of squares on it. Place the screen the same distance from the pendulum as the camera (makes calculating height and swing easier). Even better, two cameras and two screens at 90 deg. from each other.
 

Related Threads on Measure the max angle of a 3D pendulum

  • Last Post
2
Replies
32
Views
42K
  • Last Post
Replies
3
Views
16K
  • Last Post
Replies
3
Views
10K
  • Last Post
Replies
2
Views
1K
Replies
2
Views
1K
Replies
1
Views
3K
  • Last Post
Replies
4
Views
818
Replies
4
Views
1K
  • Last Post
Replies
2
Views
1K
  • Last Post
Replies
8
Views
5K
Top