1.4 Collisions in 2 Dimensions

Question 1

In 2D collisions is momentum conserved in both directions (vertical and horizontal)

Answer 1

yes

Question 2

Where are 2 dimensional collisions common?

Answer 2

Snooker or pool games

Question 3

What are the two ways of solving 2d colliisions?

Answer 3

Resolving vertically and horizontally
or
resolving along the line of impact

Question 4

When objects collide where is the momentum only transferred (what direction)?~

Answer 4

parallel to line of impact

Question 5

What is the line of impact for spherical or uniform objects?

Answer 5

One passing through centres of colliding objects

Question 6

If a stationary object is involved in a collision where will its velocity and hence movement be produced?

Answer 6

Along the line of impact

Question 7

When working with lines of impact what to do?

Answer 7

1 . Work out magnitude of velocity along parallel component
2. Work out magnitiude of velocity along perpendicular component
3 . Use pythagoras with 2 velocities calculated
4. Use trig for direction

Question 8

How can we investigate 2d collisions?

Answer 8

Using an apparatus consisting of a table with a 2 ball bearing with a camera and 2 rulers placed at right angles to each other

Question 9

How does this work?

Answer 9

• weight the ball bearings and note down the masses
• position 2 rulers at right angles to each other , place one ball bearing somewhere and the camera at birds-eye view above the table
• start the recording
• roll the second bearing at the first one so that they collide
• stop recording when both bearing comes to rest
• if we know the frame rate (time between each frame) we can work out the frames in 0.1s.