Question

Вода в реке движется со скоростью 2 м/сек относительно берега. по реке плывет плот. какова скорость плота относительно берега? относительнл воды в реке?

Answer 1

Относително берега 2 
относительно воды 0 

Answer 2

Relative Velocity of a Raft in a River

When a raft moves across a river, the velocity of the raft relative to the river is affected by both the velocity of the raft relative to the riverbank and the velocity of the river itself. This can be calculated using the concept of relative velocity.

Given: - Velocity of the river (v_river) = 2 m/s - Velocity of the raft relative to the riverbank (v_raft) = x m/s

To find the velocity of the raft relative to the river, we can use the formula for relative velocity: \[ v_{raft/river} = v_{raft} - v_{river} \]

Substituting the given values: \[ v_{raft/river} = x - 2 \]

Therefore, the velocity of the raft relative to the river is \( x - 2 \) m/s.

This calculation assumes that the direction of the river's flow is perpendicular to the direction of the raft's motion. If the angles are different, vector addition would be required to find the resultant velocity.