A geologist is studying rock layers in a river delta. The layers are buried at a shallow depth beneath sediment that the river is depositing today. Just like the sediment on top, the sediment in the rock layers was deposited by the river. How might the geologist estimate how long it took to deposit the sediment seen in the rock layers?

Aspring is used to stop a 50-kg package which is moving down a 20º incline. the spring has a constant k = 30 kn/m and is held by cables so that it is initially compressed 50 mm. knowing that the velocity of the package is 2 m/s when it is 8 m from the spring and neglecting friction, determine the maximum additional deformation of the spring in bringing the package to rest.