Dynamics is not an easy subject, in fact its one of the most dreaded subject and it is not uncommon to see many students repeating this course many times. In this blog post we will explain how to use SMART methodology to solve engineering dynamics problems.

What is SMART methodology?

The SMART methodology is a method of solving problems using the 4 step approach: S= Strategy, M=Modeling, A=Analysis, RT= Reflect & Think.

So, How to solve problems in engineering dynamics (using SMART methodology?)

Step 1. Strategy

Before we start solving a problem, we need to have a strategy. At this stage, we read the problem, and based on the quantities given and quantities to be found, we think of the concepts that we can apply to solve the problem. We first correlate the given problem to a real-life situation as with any science problem.

We can work backward also at this stage, by which we mean- if we have to find “A” and A depends on B, C, D., but C is also unknown. C depends on B, E, F, where B, E, F are known. So we can find C first. And once we find C, we can find A. We call it working backward.

For example, if the question asks us to find the speed of the bullet after piercing a hanging mass, then we think of the equation that we can use to find it. If that equation contains an unknown other than the speed of the bullet, then we need to find that unknown first, and then only we can calculate the speed of the bullet.

Step2. Modeling

Once you read and understand the problem and have a strategy in place, it is time to act. The first step is to define a system where we set things that we need to include and things that we need to exclude. Then we draw a model of the given system. If there are forces involved, draw FBDs (Free Body Diagrams). You can also write down the known and unknown quantities if it helps you visualize the problem better.

Step3. Analysis

It is the actual problem-solving step. Here we use the fundamental principles of mechanics to write equations of motion (or rest) for each body identified in the System. If we do not get enough equations to solve the unknowns, we check the System and see if we can include more bodies that we can fit in the System and get more unique equations.

If it does not work, check if there are more fundamental principles that we can apply and if the chosen System is correct. Sometimes, we need to change our strategy altogether and start afresh (i.e., start again from step 1=strategy).

If everything is correct, you just need to do the calculations (for numerical problems). We can either do everything on paper or use a calculator/computer to find the final answer.

Step4. Reflect & Think

Solving a problem is not the end of the world, and our job does not finish at step 3. We need to check if the result/answer is valid and looks plausible. For example, if you throw a ball with a speed of 10 m/s, you can not expect it to go 10 km far. If you get an answer that does not make any sense, reflect on it and think if there are things that you need to change.

If the answer to a displacement problem comes negative x, it means the distance is x, but it is in the opposite direction of the positive axis defined.

Checking the consistency of the units is also a very effective method. We can not get 10 meters for a problem that asks for the time period. This concludes-How to solve problems in engineering dynamics using SMART methodology.

(Concept Credit: Vector Mechanics for Engineers- Statics and Dynamics by Beer, Johnston. Published by McGraw-Hill Education)

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