Ballistics -- How deep does the bullet penetrate into the wood?

[duchuy]

Homework Statement

How deep in a tree would a mass m firearm projectile penetrate at velocity v0 if the frictional force between the projectile and the wood is C ?

Relevant Equations

d = mv^2 / 2C

Hi, I was given this exercice where I have to calculate the penetration distance, knowing that m = 20g, v = 300km/h and C = 750 N and I have to give the results with two significant numbers. I really thought that all I had to do was replace the values so I did :
d = (20.10^-3) x (300/3,6)^2 / 2x750 and I ended up with d = 0,0925925925...
But when I entered the answer with two significant figures = 0,093, the answer was wrong.
Please help me find me find my mistake thank you so much!
Sorry if i have misused any term, I translated this from french.

 

[PeroK]

Homework Statement:: How deep in a tree would a mass m firearm projectile penetrate at velocity v0 if the frictional force between the projectile and the wood is C ?
Relevant Equations:: d = mv^2 / 2C

Hi, I was given this exercice where I have to calculate the penetration distance, knowing that m = 20g, v = 300km/h and C = 750 N and I have to give the results with two significant numbers. I really thought that all I had to do was replace the values so I did :
d = (20.10^-3) x (300/3,6)^2 / 2x750 and I ended up with d = 0,0925925925...
But when I entered the answer with two significant figures = 0,093, the answer was wrong.
Please help me find me find my mistake thank you so much!
Sorry if i have misused any term, I translated this from french.

It looks right. It might be two decimal places, rather than two significant figures. Or, the answer in cm?

 

[duchuy]

oh my god the answer is actually in cm, thank you so much! how'd you figure that out...?

 

[PeroK]

oh my god the answer is actually in cm, thank you so much! how'd you figure that out...?

I'm clever with things like that!