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Adeleine
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Homework Statement
A 50g bullet traveling horizontally at 200 m/s embeds itself in a wooden block, initially at rest, on a horizontal surface (μk=0.1). The block slides 1.2m toward a spring and collides with it. The block compresses the spring (k=600 N/m) by 20 cm. Find the mass of the wood.
mbullet=0.05kg
v1-bullet=200
v1-wood=0
mwood= ?
mbullet+mwood= t
dwithout spring=1.2
dwith spring=1.4
k=600
x=0.02m
Homework Equations
Ff=μkmg
Wfriction=Ffxd (where d is 1.4m)
m1v1+...=m2v2...
Ek=mv2/2
Ee=kx2/2
The Attempt at a Solution
Wf=0.98t*1.4
Wf= 1.372t
mbv1+mwv1=mb+wv
.05*200=tv
v=10/t
Ek-bullet=Ek-system+Ee+Wf
1/2*.05*2002=1/2*t*(100/t)2+1/2*600*.22+1.372t
1000= 50/t + 12 +1.372t
t=720
t=mw+mb
720-0.05=mw
mw=719.95
I stated that the kinetic energy of the bullet, becomes the kinetic energy for the block and the bullet to move, plus the elastic energy and work done by friction.
Am I right in assuming this?
Thank you for the help!
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