Answer:
4th one would summarize its motion over the same time period
Step-by-step explanation:
4th one is the right answer because, since it's initially at rest this time, it would not have any speed till the 3rd second when it collids with the metallic object, when it gains the speed and kinetic energy from the object. The kinetic energy depends on the speed since the formula says: KE = 0.5mv^2, So if the velocity is zero,(I know in this case it's speed but u know what i mean), KE is zero. And if there's speed, there's KE.
Therefore, fourth one is correct!
Hope this helps!
