Tips on solving 2D Kinematic problems

[Goopy17]

Hi,
This isn't a homework question. I need help on how to go about solving 2D kinematics problems. My teacher is terrible and doesn't even teach. It seems like it should be pretty straight forward with solving these, but I'm just having a hard time. If someone could give me tips on how to go about solving, it would make my life so much easier.
Thanks!

 

[bp_psy]

Write down the given quantities at the top of the page. Write down what you are asked to do, You should read the question at least twice to be sure of what is asked of you. Begin solving the problem using symbols to represent quantities. Do not plug in numbers until the end.

 

[Ken G]

The most important thing to remember in 2D kinematics problems is that the two dimensions are entirely independent of each other. So that means you are never actually doing a 2D kinematics problem, you are always doing two 1D kinematics problems at the same time. Literally-- t is the same in the two problems, that's all that connects them.

 

[Redbelly98]

I agree with Ken G. Furthermore, for each direction (x or y), you need to know 3 of the 5 quantities (displacement, initial velocity, final velocity, acceleration, and time) in order to solve for the motion.

For projectile problems, there is a constant velocity in the x-direction. So there is really just one equation describing the x motion:

Δx = v_x·t​

In the y-direction, there is a constant acceleration of g acting downward. The kinematic equations you learned earlier in the course all apply here.

To completely solve a projectile problem you generally need to know:
(1) Two of the three quantities in the Δx = v_x·t equation, and
(2) Three of the 5 quantities involved in the y-direction: Δy, v_y,initial, v_y,final, a_y, and t. And you already know a_y.

 

[PJC01]

Hi there,

I understand that you are struggling with solving 2D kinematics problems and your teacher is not providing adequate guidance. I would be happy to offer some tips to help you approach these problems with confidence and ease.

Firstly, it is important to have a clear understanding of the basic principles of kinematics, such as displacement, velocity, and acceleration. Make sure you are familiar with the equations and their units, as this will help you to correctly set up and solve the problems.

Next, always start by drawing a clear and accurate diagram of the situation. This will help you to visualize the problem and identify the given information and unknown variables. Remember to label all the quantities on your diagram and make sure they are consistent with the units in the problem.

Once you have a clear understanding of the problem and have identified the given and unknown variables, you can start setting up the equations. In 2D kinematics problems, it is important to break down the motion into its components, typically in the x and y directions. This will allow you to solve for the components separately and then combine them to find the final answer.

Furthermore, it is important to pay attention to the direction of motion and use positive and negative signs appropriately in your calculations. This will ensure that you get the correct magnitude and direction for your final answer.

Lastly, practice makes perfect. The more you practice solving 2D kinematics problems, the more confident you will become in your abilities. Don't hesitate to ask for help from your teacher, classmates, or even online resources if you are still struggling.

I hope these tips will help you in solving 2D kinematics problems. Remember to stay organized, pay attention to units and direction, and practice regularly. Good luck!