Trying to understand how to make Motion Diagrams

[Dko]

Trying to do my first Physics home work assignment for college and I'm not really making any headway. He went thru the martial so fast while throwing in calculus that I'm not sure if I do or don't need.
My main problem with Motion Diagrams is I'm not sure how accurate I'm supposed to be and how do I get that level of accuracy I need?
The problem I'm on bellow, is really getting me because I don't know how to start. Should I show 35 meters of movement and the reaction time before the deceleration?

Homework Statement

"The driver of a car traveling at 35 m/s suddenly sees a police car. The driver attempts to reach the speed limit of 25 m/s by accelerating at 2.5 m/s^2. The driver has a reaction time of 0.55 s. (The reaction time is the time between first seeing the police car and pressing the brake.)

Homework Equations

The Attempt at a Solution

I really don't know how I would show a solution on here.

Hope my problem makes sense.

 

[berkeman]

Trying to do my first Physics home work assignment for college and I'm not really making any headway. He went thru the martial so fast while throwing in calculus that I'm not sure if I do or don't need.
My main problem with Motion Diagrams is I'm not sure how accurate I'm supposed to be and how do I get that level of accuracy I need?
The problem I'm on bellow, is really getting me because I don't know how to start. Should I show 35 meters of movement and the reaction time before the deceleration?

Homework Statement

"The driver of a car traveling at 35 m/s suddenly sees a police car. The driver attempts to reach the speed limit of 25 m/s by accelerating at 2.5 m/s^2. The driver has a reaction time of 0.55 s. (The reaction time is the time between first seeing the police car and pressing the brake.)

Homework Equations

The Attempt at a Solution

I really don't know how I would show a solution on here.

Hope my problem makes sense.

Welcome to the PF.

I would start this problem by drawing a graph with velocity on the vertical axis and time on the horizontal axis. Draw the 35m/s initial velocity starting before time t=0 (to the left of the vertical axis), and then at t=0, that's when he sees the police car. But there is reaction time before he starts decelerating, so the 35m/s line continues for a bit, and then starts decreasing due to the deceleration...

 

[TheLil'Turkey]

I recommend ignoring the reaction time of the driver and just starting by calculating how long it will take for the car to decelerate (or accelerate backwards) from 35 to 25 m/s with the acceleration given in the problem. Do you know how to do that?
edit: If you can do that then move on to berkeman said above.

 

[Dko]

Thanks. I think I have a handle on things now. Youtube helped some as well.

 

[asteriatic]

First of all, don't worry if you're struggling with understanding Motion Diagrams. It's completely normal for students to have difficulty with new concepts in physics, especially in college. It's important to remember that learning takes time and practice, so don't be too hard on yourself.

To start, Motion Diagrams are used to visually represent the motion of an object over time. They can help us understand the velocity and acceleration of an object, and they are a useful tool in solving problems like the one you have been given. The key to creating accurate Motion Diagrams is to pay attention to the details and be as precise as possible.

In terms of accuracy, the level of detail you need to include in your Motion Diagrams will depend on the specific problem you are solving. In this case, you should include the initial velocity of 35 m/s, the acceleration of 2.5 m/s^2, and the final velocity of 25 m/s. You should also include the reaction time of 0.55 seconds before the driver begins to decelerate. This means that your Motion Diagram should show the car traveling at a constant velocity of 35 m/s for 0.55 seconds, followed by a decreasing velocity until it reaches 25 m/s.

As for the problem itself, the key is to break it down into smaller steps. First, calculate the distance the car travels during the reaction time of 0.55 seconds (using the initial velocity of 35 m/s). Then, calculate the remaining distance the car needs to travel to reach the speed limit of 25 m/s (using the acceleration of 2.5 m/s^2). Finally, add these two distances together to get the total distance traveled by the car.

I hope this helps you understand how to approach Motion Diagrams and solve the problem given. Remember to take your time and practice, and don't hesitate to reach out to your professor or classmates for help if needed. Good luck!