# Confused with direction in this problem

• Kinto
In summary, the problem involves a car moving initially at 32 km/h[N], turning a corner and continuing at 32 km/h[W]. The turn takes 3.0s to complete. The question asks for the change in velocity and average acceleration during the turn. While the velocity and acceleration values were correctly calculated, there was confusion about the direction, with the answer in the book stating SW instead of NW. However, this is due to the acceleration vector being perpendicular to the line of motion and pointing towards the inside of the circle, resulting in a SW direction.

#### Kinto

Problem states that the object is moving North then turns and continues West. The answer on the book says final direction is SW. Shouldn't it be NW?

Thanks.

I don't quite get your question, or rather, the question that you're having problems with. Can you please elaborate on it?

The exact wording of the problem in the book is:
A car, moving initially at 32 km/h[N], turns a corner and continues at 32 KM/h[W]. The turn takes 3.0s to complete. Find (a) change in velocity and (b) the average acceleration during the turn.

I got the velocity and the acceleration. But I am having problem with the direction. Since it's going North then it turns west. Shouldn't it be North West? The answer in the book have it as SW.

Originally posted by Kinto
I got the velocity and the acceleration. But I am having problem with the direction. Since it's going North then it turns west. Shouldn't it be North West? The answer in the book have it as SW.
The value of the velocity did not change, just its
direction. This is an indication of centripatal acceleration.

Live long and prosper.

Direction is part of the "value of velocity".

Anyways, how you get the change in velocity and the average acceleration?

I've used the head-to-tail method and got the squared of both velocity to get the resultant. And use the resultant velocity to get the acceleration.

Now trying to picture it. Is it accurate to say direction is southwest because during the turn, the car direction is actually moving southwest from it's original direction of North?

Right; the change vector is pointing southwest.

Originally posted by Kinto
I've used the head-to-tail method and got the squared of both velocity to get the resultant. And use the resultant velocity to get the acceleration.

Now trying to picture it. Is it accurate to say direction is southwest because during the turn, the car direction is actually moving southwest from it's original direction of North?
Yes the resultant velocity vector is NW but the change is SW. What textbook are you using?

It's an old textbook. Fundamentals of Physics. I am using the problem there for practice.

In your original post you said "Problem states that the object is moving North then turns and continues West. The answer on the book says final direction is SW. Shouldn't it be NW?"
My reaction was "no, the final directions is West!"

Your error was interpreting "acceleration vector" as "final direction".

Think of it as turning in a circle. Since the speed remains constant the acceleration vector is perpendicular to the line of motion, pointing toward the inside of the circle.

## 1. What does it mean to be "confused with direction in this problem"?

Being confused with direction in a problem means that you are having difficulty understanding the steps or process required to solve the problem. You may be unsure of where to start or how to proceed, leading to confusion and uncertainty.

## 2. How can I overcome confusion with direction in a problem?

One way to overcome confusion with direction in a problem is to break it down into smaller, more manageable steps. This will help you focus on one aspect at a time and make the problem less overwhelming. You can also try discussing the problem with a peer or seeking guidance from a teacher or tutor.

## 3. What are common reasons for becoming confused with direction in a problem?

There are many reasons why someone may become confused with direction in a problem. These can include a lack of understanding of the concepts involved, not paying attention to the problem, or trying to rush through the problem without fully understanding it.

## 4. How can I prevent confusion with direction in a problem?

To prevent confusion with direction in a problem, it is important to read the problem carefully and make sure you understand what is being asked. Take your time and think about the problem before attempting to solve it. It can also be helpful to review any relevant concepts or formulas before starting the problem.

## 5. Are there any strategies or techniques for improving my direction in problem-solving?

Yes, there are several strategies and techniques that can help improve your direction in problem-solving. These include practicing regularly, seeking help when needed, and using visual aids or diagrams to better understand the problem. Additionally, taking breaks and approaching the problem with a clear and focused mind can also be beneficial.