I How hard of a Hit force does it take to make a mass jump?

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To determine how high a steel rod or ball will jump when struck, the discussion emphasizes the importance of understanding the parameters of the collision, such as the mass of the impacting object, its speed, and the elasticity of the collision rather than just the force applied. A formula based on momentum and kinetic energy is recommended for calculating the height achieved after impact, rather than relying solely on force measurements. The conversation also highlights the need for precise definitions of terms like peak and average force, as well as the significance of the collision's duration. Participants suggest using kinematic equations to analyze the projectile motion of the object post-impact. Overall, a comprehensive approach that factors in various physical principles is essential for accurate calculations.
  • #31
jbriggs444 said:
Guessing that you meant to write that a block is moving upward at 2.18 feet / sec^2, unimpeded by anything other than gravity.

The easy way to approach this from first principles is to start by computing how long it will take for the object to slow to a stop. That result can be obtained by $$t = \frac{v}{a}$$where ##t## is the time it takes, ##v## is the initial upward velocity and ##a## is the downward acceleration of gravity. In units of feet and seconds, the acceleration of gravity is approximately 32.2 feet per second squared.

Since the acceleration is uniform, the average velocity is the mean of the initial velocity and the final velocity. The final velocity is zero, so this simplifies to$$v_\text{avg}=\frac{v}{2}$$where ##v_\text{avg}## is our sought-after average velocity and ##v## is the given 2.18 feet per second^2.

The upward distance travelled will be the product of the two:$$h = v_\text{avg} t = \frac{v}{a} \frac{v}{2} = \frac{v^2}{2a}$$If we use a calculator we can calculate:

Elapsed time: 67 milliseconds.
Average velocity: 1.09 feet per second
Height gained: 0.737 feet = 0.885 inches
thats not in C or C++?
 
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  • #32
MIKES279 said:
thats not in C or C++?
Ideally, it would be in "number 2 pencil and a sheet of paper". However, all I have handy is this forum software that uses ##\LaTeX## and a Windows calculator.
 
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  • #33
MIKES279 said:
thats not in C or C++?
Nothing here needs to be in a computer program. It's all simple formulas that can be done quickly with pen and paper and a calculator. If anything a spreadsheet program like Excel would be just fine if you're looking for some barebones automation. You certainly don't need to go with C or C++ unless you plan on writing a serious program or you're practicing your coding.
 

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