- #1
anubis01
- 149
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Homework Statement
A 18.00 Kg lead sphere is hanging from a hook by a thin wire 3.80 m long, and is free to swing in a complete circle. Suddenly it is struck horizontally by a 4.50kg steel dart that embeds itself in the lead sphere.
a)What must be the minimum initial speed of the dart so that the combination makes a complete circular loop after the collision
Homework Equations
v1=(ms+md/md)v2
The Attempt at a Solution
d=dart s=sphere
mdvd=(ms+md)v2
vd=(ms+md/md)v2
v2 makes a complete circular loop so
1/2(md+ms)v22=(md+ms)2gr
v2=sqrt(4gr)
vd=(ms+md/md)sqrt(4gr)
vd=(18+4.5/4.5)sqrt(4*9.8*3.8)
=5*12.204=61.02m/s
vd=61.02m/s
Now my problem with this is the TA said I took all the right steps to solve this equation but I'm still getting an error using masteringphysics and I have gone over my work for errors 10 times by now. Is the work I did correct or am I missing something in my calculations.
Thanks in advanced for any assistance.