building a device to shoote a plastic hockey puck with a lever (think pinball) attached to a bungie cord. How much force is needed to propel a plasic hockey puck 30 feet or 40 feet or 50 feet - what formula should I use? Can I calculate the force by how much the bungie cord stretches?
To calculate the force needed to propel a plastic hockey puck a certain distance using a lever attached to a bungee cord, you will need to consider a few factors.
Firstly, the force required will depend on the desired distance, as well as the mass of the hockey puck. To determine the force needed, you can use Newton's second law of motion, which states that force (F) is equal to mass (m) multiplied by acceleration (a):
F = m * a
In this case, acceleration can be calculated using the formula for projectile motion, which is given by:
a = (2 * d) / t^2
where d is the distance and t is the time it takes for the puck to reach that distance. Note that time can be obtained by measuring it experimentally or estimating it based on the initial speed of the puck.
Now, as for calculating the force based on the extension of the bungee cord, it is a more complex matter. The force applied by the bungee cord depends on its spring constant (k) and the amount of stretch or extension (Δx). According to Hooke's Law, the force (F) exerted by the bungee cord is given by:
F = k * Δx
By measuring the extension of the bungee cord, you could calculate an approximate force using this formula. However, note that the force required to attain the desired distances may not be accurately determined solely based on the bungee cord's stretch. Other factors such as friction, air resistance, and the lever mechanism itself will also affect the force needed.
To summarize, the formula to calculate the force required to propel a plastic hockey puck a certain distance would involve using Newton's second law of motion with the projectile motion formula for acceleration. While the bungee cord's extension can give you a rough estimate of the force, it may not be accurate enough due to other factors involved.