Car and VehicleSTEM experiments
Cars and other types of vehicles are rich veins of STEM experiments. From the simplest toy car to the most advanced electric vehicle, there are hundreds of experiments that you can do at home to underline and test their core principles.
Even students as young as first grade can undertake experiments on the ideas that underpin how and why cars move.
Moreover, if you’re planning on conducting STEM experiments with students, you can also use this as an opportunity to teach the scientific method, utilizing the six steps to not just show them how to do these experiments, but experiments in general.
The scientific method is the bedrock of science experiments and it determines how best to do an experiment to make the results accurate, repeatable, and prove the connection between variables.
The six steps to follow in an experiment – from beginning to end are:
1Ask a question
All STEM experiments begin with a question. Ultimately you are trying to determine what the impact is of x on y. Depending on the age of the student, you may notice something in the wider world and try and work out why that is the case (for example, why cars have four wheels). Older students will have more advanced questions. However, this is the starting point for your experiment.
Allow your student to probe the question themselves. Ultimately, the experiment
is the means by which they find the answer, so you don’t need to tell them!
At a school and college level, research involves looking through previous experiments and reading through papers online or in a textbook. However, if you’re working with younger students, or simply looking to do an educational activity on a break from school, it’s unlikely you’ll get out the textbook. Instead, research can involve considering other examples the student is familiar with.
For example, if your student asks you why cars have four wheels, ask them to think about vehicles that don’t have four wheels, such as larger trucks, or even bicycles. Thinking about how these are different will help them build some context around their original question.
3Make a hypothesis
The hypothesis stage is important and can actually be simpler than it sounds. The question to ask your student is: “Why do you think it is like that?” or “What do you think will happen?” In both of these cases, the student will develop a hypothesis that helps them to construct their experiment.
The hypothesis is what will be tested with the experiment, so it doesn’t matter if it’s right or wrong (although students may need some ‘guiding’ to make sure they’re not testing totally unconnected variables).
4Test your hypothesis
Testing your hypothesis is your experiment. Ultimately, an experiment is designed with the ideal goal of attributing cause and effect to two variables (if I do x, then y will happen). In order to test this, you need to create an experiment that removes extraneous variables; if you’re feeling advanced you can also develop a control group to better test that the outcome you get is cause and effect – rather than just correlation.
You can always adjust your methodology as you go, particularly if this is a ‘fun’ experiment.
5Draw a conclusion
Once you’ve done your experiment (being sure to repeat it a few times to prevent erroneous or anomalous results) you can draw conclusions. This involves going back to your hypothesis and determining whether
it was correct or not, or answer the core question outlined.
At this stage, you can have your student think about why that may be the case. This will engage them in thinking in a truly scientific manner and may require additional answers.
6Share your results
Although this step is less important for ‘fun’ experiments, you can use this as an opportunity to ask your student what experiment they would run next time. This allows them to think about the methodology they used, as well as alternative experiments that they might run.
These steps are the same regardless of the experiment you are doing. Teaching these to your students will ensure that they understand how and why they are operating in a certain way. After all, if you’re attempting to foster an interest in STEM, then this is a process that they will need to understand.
Furthermore, you can also discuss the idea of dependent and independent variables, as well as things like control groups. Each of these is a key piece of terminology with important consequences for designing an experiment and drawing conclusions.
These terms and concepts may be a little advanced for younger students, so you may only need to engage with them implicitly.
Working out how a car propels itself is a fundamental question for students of all ages. Depending on the grade level of the student, they may have a rudimentary understanding of the internal combustion engine, but not know how that propels a car forward. For younger students, they simply may not know how a car moves at all.
Using equipment commonly found in most kitchens, you can show students how chemical reactions can cause energy to be released, and how this energy can propel a car to move forward.
Construct your ‘vehicle’ by taping a medium size plastic water bottle to a set of toy wheels. The bottle should have a long drinking nozzle. Check to see that the vehicle moves freely (i.e. the wheels don’t get stuck, and the bottle doesn’t drag on the ground).
Place the soda-wrapped tissue in the bottle and seal the lid right away. Shake the bottle to allow the soda to react with the vinegar.
Wrap a small amount of baking soda in a light tissue (roughly ¼ of an ounce, although quantities do not need to be exact).
In the bottle, add 3 or 4 oz. of vinegar. You can also add 2 oz. of water to provide some weight (and therefore some thrust).
Lay the vehicle down and open the sports cap. The expulsion of the solution will force the vehicle to move forward (it’s best to do this experiment outside!).
The vinegar (acetic acid) reacts with the baking soda (sodium bicarbonate) to create carbon dioxide and sodium acetate. The carbon dioxide and sodium acetate expand and create pressure within the bottle.
Once the sports cap is opened, the expulsion of the solution causes an equal and opposite reaction (as per Newton’s laws) which will provide thrust to the vehicle.
This principle is the same as that in rocket ships.
Students may have questions about why it is necessary for cars to be shaped the way they are, or why we use a particular type of road surface. Depending on the question, there are experiments that you can use to show how air resistance and/or friction cause a vehicle to slow down.
If you have a more advanced student, you can talk about Newton’s laws, and why friction is necessary to stop a car (hence the way that brakes work in a vehicle). You can also show how different road surfaces impact driving.
Depending on whether you are testing air resistance or friction, you will follow a slightly different methodology.
Create a ramp for a small toy car.
If you are testing friction, cover the ramp with sandpaper (for different levels of friction, use multiple different pieces of sandpaper, each with a different grit size).
If you are testing air resistance, place a fan at the end of the ramp (albeit at a distance that the car would already have stopped on its own).
Run the car down the ramp without sandpaper/without the fan being on. Be careful not to ‘push’ the car (i.e. don’t apply any additional force when releasing it). Make a mark of how far it traveled.
Repeat the trip with the fan on, or the different sandpaper coverings. Keep a record of how this impacted the distance traveled.
If your experiment works well, you will see that both air resistance and a high-friction surface cause the car to slow down more quickly and achieve a shorter distance traveled. This demonstrates the nature of opposing forces, and how cars move better when they have less force applied to them that checks their motion. This is consistent with Newton’s laws of motion.
If you have run the air resistance experiment, you can try it with different types and weights of cars to see how that impacts the force of air resistance, and how this can be applied to car design.
Anyone who has traveled on the road knows that not all drivers behave the same way, and nor do any drivers behave consistently. Driving is very much context-dependent. For older students, observing drivers is a great opportunity to think about the science of human behavior. This is an underrated but important aspect of STEM.
By looking at the way that drivers behave, and how this behavior changes, a student can learn about how and why roads, traffic signals, and cars are designed in particular ways. For example, a student can measure how context affects driver decision-making.
Find a stop sign on an intersection where you can comfortably observe traffic.
With a clipboard and a pen and paper, make a note of how many divers come to a complete stop at the stop sign; how many make a ‘rolling stop,’ and how many simply drive through.
Repeat your results on a weekend afternoon and during rush hour (8-9am or 5-6pm) and determine how the results have changed.
For an advanced experiment (you may need a second person for this) make note of the different car makes and models, or even car types (such as SUVs) and measure the same data. This will allow you to draw conclusions on driver behavior.
This experiment will also allow students to get a sense of how research is conducted at a more advanced level.
For students who have experience with experiments in classrooms, conducting research in the field will also show that it is sometimes difficult to draw objective conclusions when dealing with the social sciences. This experiment is a more advanced sociological experiment and is based on a student being comfortable with taking data and extrapolating out results.
However, the method that they use will show that the more data points they have, the more they can attribute conclusions. This, in itself, is a valuable conclusion to learn.
They will also learn about the nature of driver decision-making, and in particular how different times of day (i.e. different contexts) cause drivers to operate in different ways.
Ultimately, cars and vehicles are central to everyday life in the modern world. For the curious student, therefore, there are lots of questions that can emerge simply by interacting with cars and other vehicles.
As a parent or educator, teaching a student how they can find the answers to their own questions is a critical step in empowering students to think for themselves.
After all, it is important not to teach students what to think, but how they think. Giving them the scientific method and using this as a model for achieving the answers they seek will be a major cognitive tool for them, regardless of their age.
You can create experiments geared around all four constituent parts of the STEM concept. In fact, most experiments will cover more than one (and many will cover all four).
Working out how cars move, what slows them down, and how drivers behave in a certain way will give students the ability to understand fundamentals about the world around us. Moreover, they will also learn how STEM works in general.
This will allow them to develop their own hypotheses, think about the cause and effect of other things, and generally boost both their understanding of, and curiosity towards, the world around them.
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