Andy carried out the experiment below. He rolled the iron ball down the wooden plank and recorded the time taken for the ball to travel from A to M and from M to V before and after object X was placed below the wooden plant as shown below. The results were then recorded in the table below.
|Time taken to travel from A to M (s)||Time taken to travel from M to V (s)|
|Without object X||15||26|
|With object X||11||34|
Which of the following is/are possible explanation(s) for the difference in the time taken for the ball to travel from one point to another point?
(You may select more than one answer)