Possible Error

What are possible sources of error in this physics experiment?

We had to measure the horizontal distance traveled by a marble which rolled down a tube and through photogates off a table and onto the floor. The marble hit a sheet of carbon paper and left a mark which we measured from the bottom of the table. So what are some possible sources of error? My measured and predicted values had a 4.6% percentage difference.

Possible sources of error could include anything you didn’t factor into your calculations (Because you didn’t say how you calculated your predicted values I’m just gonna list everything I can think of):

Friction with the table which would slow the ball down

Drag from the air (Inluding any drafts that could shift the position of the ball)

Mass (How exact was your measurement of the ball’s mass? – also if you’re using basic kinematic equations the mass is considered negligible…in reality it’s not so that’s also a source of error)

The accuracy of the method which you used to measure any distances (if you use a meterstick you can not really get any more accurate that 0.5 mm)

The ball’s rotational inertia would also slow it down – if you didn’t factor it in already…

This is all I could think of off the top of my head but there very well could be more.
Hope this helps

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