The table below shows data of sprints of animals that traveled 75 meters. At each distance marker, the animals' times were recorded. Which animal moves with accelerated motion?

Time at Distance Markers

Animal 25 meters 50 meters 75 meters

Animal 1 3 seconds 5 seconds 6 seconds

Animal 2 4 seconds 8 seconds 12 seconds

Animal 3 3 seconds 6 seconds 9 seconds

Animal 4 10 seconds 20 seconds 30 seconds

Animal 1

Animal 2

Animal 3

Animal 4

Animal 1

Explanation:

For an animal moving with uniform motion ( = constant speed, no acceleration), the distance covered in equal time intervals is always the same.

From the table, we can see that this situation occurs for animal 2, animal 3 and animal 4. In fact, for all these 3 animals, the time interval to cover each block of 25 meters remains constant; in particular:

- Animal 2 always takes 4 seconds to cover each 25 m block

- Animal 3 always takes 3 seconds to cover each 25 m block

- Animal 4 always takes 10 seconds to cover each 25 m block

The situation is different for animal 1; in fact:

- it takes 3 seconds to cover the first 25 m

- it takes (5-3) = 2 seconds to cover the second block of 25 m

- it takes (6-5) = 1 seconds to cover the third block of 25 m