Transcript 141.review
Exam III Review
JH.141
At the explosion point, the momentum of the forward piece is the same as the
momentum before explosion doubling the velocity (since mass is halved)
It also doubles the range. Find time from y motion then use it to find pre-explosion
range then double that range
Key Idea: linear speed at the edge is identical
Way 1: balance torques around the edge of the lower brick
a1: put the mg at the edge (i.e. L/2) this makes this torque zero
a2: put the mg of the top at the edge and support force
mg (a2) = (L/2- a2) mg a2 = L/4
2mg(a3) = (L/2 – a3) mg a3 = L/6
Way 2: COM from the right edge is calculated