Relative Velocity and River Boat Problems

This video discusses the concept of relative velocity. The concept is applied to explain the analysis of the motion of planes moving amidst winds and the motion of boats heading up, down, and across a river in the presence of a current.

The topic of Adding Right Angle Vectors is discussed at length in another video:

You can find more information that supports this video on our website.

Student Action Plan includes:

Calculator Pad, Vectors and Projectiles, Q#19 - Q#21:

Physics Interactive - River Boat Simulator

Concept Builder - Relative Velocity
As of this writing, the Relative Velocity Concept Builder has not yet been completed.

Tutorial on Relative Velocity and River Boat Problems

Other Videos on Vectors and Projectiles can be found at ...

And finally, the Home Page of our complete Physics Video Tutorial is located at ...

[pomme]

I could cry, I finally understand... Thank you so much this is the best video on this topic

[zn]

Thanks for the video! I was wondering, to find the displacement of the boat downstream, why we wouldn’t use the boat’s velocity but instead use the velocity in the down direction?

[kingseethambaram]

The best class ever I listened better than physics wallah

[PhysicsclassroomVideos]

In this case the boat must head north of East. The 14 m per second is at an angle to East and is hypotenuse of the triangle. The 8 m/s is the vertical side of the triangle and you want to find the horizontal side of the triangle which is directed due east

[nabilahsaleh]

I would highly appreciate your response, please.
the below question is similar to one of your questions, but how do I relate the 200 seconds to the solutions steps?

"Assume now that the boat wants to cross the river in exactly 200 seconds, and wants to reach a point on the far shore directly opposite the launch point. What is the magnitude and direction of the velocity vector the boat must have through the water? Please specify the direction by drawing a picture and labeling a relevant angle."

[nabilahsaleh]

Thank you for your explanation.
If the boat attempts to sail straight across the water at its maximum speed, how far down the shore will it drift due to the current? In this question do I use the same steps as your solving distance steps?

[mantalope]

How Do I know which side is the resultant velocity?

In a question like this

A boat can travel at a max speed of 14 m/s in still water. It must travel due East across a 120 m wide river, which has a current flowing at 8.0 m/s South.


The resultant velocity is not the hypotenuse so I can I tell which side?

[wakimaki]

Thank you! This really clear things up for me

[mood]

why do you use the time taken from directly crossing the river and use it as the same time when the boat moves downstream? they didnt specify the length of the river so it should be wrong

[bradensmith]

How do I find the velocity of the water?

[schoolofscienceglobal]

What if you're given the velocity of the boat in still water, plus the velocity of the water current down stream?. Please I need you to do a question of that That's the only confusion I have now....Questions involving velocities of boats in still water... Thanks in advance

[meenakshisivan]

In the question that you've asked us to practice it ia given that it's the speed of boat with respect to the water.
So the resultant velocity of the boat must be its velocity related to ground right?
But why didn't we consider it that way.
Could you please give an explanation.

[nvr]

Hi. Thanks for all your wonderful videos. Request your help on a particular problem from Indian CBSE Board 11th std on relative velocity. In this, the situation is that rain is falling vertically at a certain velocity. A person is walking / riding at a certain velocity, holding an umbrella. The ask is to find the angle at which the umbrella has to be held. I found this problem fundamentally confusing. The rain direction is unlikely to be affected by the speed of the person / object moving on the road, so would it not be wrong to add these 2 vectors and find a resultant vector and then an angle and say that the umbrella has to be held at an angle. Kindly advise. Thanks.

[COcdump.]

1. Your car will serve as a boat. Write a brief statement to explain how boat's speed can be determined.?

[anilsinha]

Will you be adding rotational physics videos ?