Irodov's Problems in General Physics

[abhikesbhat]

Homework Statement

A motorboat is going downstream overcame a raft at a Point A; t=60 min later it turned back and after some time passed the raft at a distance l=6km from point A. Find the flow velocity assuming the duty of the engine to be constant.

Homework Equations

Average Velocity, Average Speed, Displacement

The Attempt at a Solution

I drew a picture and labeled everything. I know the average velocity of the motorboat is 6km per hour.

 

[jbsteele]

I know the displacement is 6km. What I am having trouble with is finding the average speed of the motorboat.Thanks for any help

 

[nlightner]

Then I used the equation:
Average Velocity = Displacement / Time
to solve for the displacement, which is the distance traveled by the motorboat. Since the motorboat traveled downstream for 60 minutes and then turned back, I calculated the total time as 120 minutes or 2 hours. Therefore, the displacement would be 6km/hour * 2 hours = 12 km.
Now, using the equation:
Average Velocity = Displacement / Time
I can solve for the flow velocity, which is the speed of the water. Rearranging the equation, I get:
Flow Velocity = Displacement / Time
Plugging in the values, I get:
Flow Velocity = 12 km / 2 hours
Flow Velocity = 6 km/hour
Therefore, the flow velocity is 6 km/hour.
This solution assumes that the motorboat and the raft are moving in a straight line and that there are no other external factors affecting their motion. If the motion is more complex, additional equations and variables may need to be considered. Additionally, it is important to note that the duty of the engine being constant is an idealized assumption and may not always be accurate in real-world situations. Further experiments and measurements may be necessary to confirm the calculated flow velocity.