Finding the Center of Mass for a Pinewood Derby Car

In summary, to determine the center of mass of a pinewood derby car, there are a few methods that can be used. One suggestion is to measure the shape and mass of each component and calculate their individual center of gravity, then calculate the overall value. Another method is to balance the finished car on a knife edge. There is also a discussion about where the weight in the car should be placed, with the general consensus being as low and far back as possible. To find the center of mass, one can hang the car from a string and find the intersection of two points, or use three different hanging points for a more accurate measurement. Ultimately, the most important design consideration for a pinewood derby car is the wheel friction, followed by
  • #1
bart Sherer
2
0
I am trying to determine the center of mass of a pinewood derby car. Any suggestions on how this can be done?
 
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  • #2
On paper, my measuring the shape and mass of each component - calculating their individual CofG then calculating the overall value.
Or just balance the finished car on a knife edge.
 
  • #3
Thanks. There is also a lot of discussion as to where the weight in the car shoud be placed. I assume the weight should be placed as low as possible and as far back on the vehicle as possible. Your input is appreciated.
 
  • #4
Hang the car from the middle of a string, the hanging (free) end of the string will pass through the cm. Do this from 2 different points, the intersection is your cm.
 
  • #5
To find the center of mass, you actually need *3* different 'hangings' because the car is 3-dimensional. Two will identify the line that passes through the center of mass, the third will reduce it to a point.

In any case, IIRC, the number 1 design consideration is the wheel friction. The wheels must spin freely and be lubricated. Then, the weight and aerodynamics come into play.
 

FAQ: Finding the Center of Mass for a Pinewood Derby Car

What is the center of mass for a derby car?

The center of mass for a derby car is the point at which all of its mass can be considered to be concentrated. It is the point where the car will balance if supported at that point.

Why is the center of mass important for a derby car?

The center of mass is important for a derby car because it affects the car's stability and handling. A car with a lower center of mass will be more stable and less likely to tip over, while a car with a higher center of mass may be more prone to tipping and have less control.

How do you find the center of mass for a derby car?

The center of mass for a derby car can be found by balancing the car on a point and marking that point, or by using mathematical formulas to calculate the center of mass based on the car's dimensions and distribution of mass.

Can the center of mass be changed for a derby car?

Yes, the center of mass for a derby car can be changed by adjusting the distribution of weight in the car. Adding or removing weight from different areas of the car can shift the center of mass and affect its stability and handling.

How does the center of mass affect a derby car's performance?

The center of mass plays a crucial role in a derby car's performance. A lower center of mass can improve stability and handling, while a higher center of mass can make the car more prone to tipping. It is important to find the optimal center of mass for a derby car to achieve the best performance on the track.

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