What is the speed of the river in km/hr?

In summary, the boat takes 3.1 hours to travel 15 km down the river and 5.1 hours to travel the same distance upstream. It is traveling at a rate of 4.84 km/hr down the stream and 2.94 km/hr up it. To determine the river's speed, you can use the formula d=rt and work backwards by subtracting the boat's speed from the total speed when traveling upstream.
  • #1
ijd5000
7
0
a boat takes 3.1 hours to travel 15 km down a river, then takes 5.1 hours to travel the same distance upstream. how fast is the river traveling.

I found the boat is traveling at 4.84km/hr down the stream and 2.94 km/hr up it. not sure where to go next.

Any help would be appreciated.
 
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  • #3
Let's say the river's speed is 1 kph and the boat's speed is 2 kph then the boat will travel downstream at 3 kph and upstream at 1 kph. So when you go downstream you add the speeds, but when going upstream, you subtract the river's speed from the boat's speed. Try working that backwards.
 

1. What is the definition of kinematics in the context of a boat question?

Kinematics refers to the study of motion, specifically the position, velocity, and acceleration of an object without considering the causes of its motion.

2. How can you apply kinematics to a boat question?

In a boat question, kinematics can be used to calculate the speed, direction, and acceleration of a boat, as well as its position at a given time.

3. What are the key principles of kinematics that can be used to solve a boat question?

The key principles of kinematics include displacement, velocity, and acceleration. These can be used to determine the boat's position, speed, and changes in speed over time.

4. How can you use kinematics to compare the motion of two boats?

By analyzing the displacement, velocity, and acceleration of two boats, their relative motion can be compared and their positions and movements can be predicted.

5. What are some common equations used in solving a kinematics boat question?

Some common equations used in kinematics boat questions include the distance formula (d = vt), the average velocity formula (v = d/t), and the acceleration formula (a = (vf - vi)/t).

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