- #1
sunny0302
- 6
- 0
I have been out of school for a few years so my physics is rusty. I need help figuring something out for my job. I need to know how high I must drop an object so that it hits the ground with an impact of 1000g's. The object is a cylindar and weighs 2lbs.
I have been confusing myself. I know that the object will fall with 1g acceleration. I think need an equation that allows me to find the instantaneous acceleration at the moment of impact. I think I can assume an infinitely hard ground for now. I have found that instantaneous acceleration is delta v/delta t where t->0.
~~~~
If a=9806 m/s^2 then as t-->0, the velocity would be 9806 m/s?
So then I think I need to use another equation to back out the height
I found this equation for free-fall with no air resistance but I'm not sure it helps.
y(t)=-1/2*g*t^2 + v_o*t + y_o
I found this equation for impact vel just before impact = sqrt(2*g*h). But if I set it equal to 9806 I get h=4,903,000 meters...that seems very high.
I am also worried when the equations don't take mass into account.
~~~~~
Another option I thought of:
F=ma
F=(.907 kg*9806m/s^2)
F=8894N
And then I would need some sort of equation that let's me back height out of Newtons.
Can anyone help me? I'm going in circles.
I have been confusing myself. I know that the object will fall with 1g acceleration. I think need an equation that allows me to find the instantaneous acceleration at the moment of impact. I think I can assume an infinitely hard ground for now. I have found that instantaneous acceleration is delta v/delta t where t->0.
~~~~
If a=9806 m/s^2 then as t-->0, the velocity would be 9806 m/s?
So then I think I need to use another equation to back out the height
I found this equation for free-fall with no air resistance but I'm not sure it helps.
y(t)=-1/2*g*t^2 + v_o*t + y_o
I found this equation for impact vel just before impact = sqrt(2*g*h). But if I set it equal to 9806 I get h=4,903,000 meters...that seems very high.
I am also worried when the equations don't take mass into account.
~~~~~
Another option I thought of:
F=ma
F=(.907 kg*9806m/s^2)
F=8894N
And then I would need some sort of equation that let's me back height out of Newtons.
Can anyone help me? I'm going in circles.