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marshall4
Nov29-03, 03:44 PM
How do i find the force constant of a spring with a Newton meter?
Do i graph the force applied vs. distance of stretch? What is on the x-axis, what is on the y-axis?

How do i find an equation for the amount of skretch needed for on spring on a projectile, with the horizontal distance, angle of the projectile, mass and force constant given?

PiRsq
Nov29-03, 04:24 PM
What kind of text book are you using in your school?

ShawnD
Nov29-03, 04:37 PM
Originally posted by marshall4
How do i find the force constant of a spring with a Newton meter?
Do i graph the force applied vs. distance of stretch? What is on the x-axis, what is on the y-axis?
F = kd
k = F/d
Now that you know the formula, it's easy to figure it out. Plot force on the Y axis and displacement on the x axis. The slope of the graph will give you the k value.


Your second question is difficult to understand. Can you reword it or say it differently?

marshall4
Nov29-03, 04:45 PM
Originally posted by PiRsq
What kind of text book are you using in your school?

Nelson Physics 12
Why?

marshall4
Nov29-03, 04:53 PM
Originally posted by ShawnD



Your second question is difficult to understand. Can you reword it or say it differently?

I'm launching a spring off the end of an angled launch pad (projectile) at angle Өtheta, i want to find how long i have to skretch the spring in order for the spring to go x metres in the horizontal distance.

i think i use the equation ½mv²=½kx² to find the velocity. Then I use that velocity in the equation d=[v²sin2(theta)]/g, to find the horizontal distance. Does that sound right, or is there an easier equation?

AD
Nov29-03, 06:29 PM
Combine the equations to get the result

Range = (kx2 sin 2θ)/mg

I can't see it getting any easier.

PiRsq
Nov29-03, 09:27 PM
Checkout Sample Problem #4 on pg 209