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yttuncel
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Homework Statement
A small wooden block, of mass M, lies in the middle of a horizontal table of length L
and height h above the floor. The coefficient of kinetic friction between this block
and the surface of the table is μ. A bullet, of mass m, is shot with a horizontal
velocity into the block. As a result, the block (with the embedded bullet) starts
moving across the table and finally lands on the floor a horizontal distance D from
the edge of the table. Use this information to find the speed of the bullet.
Homework Equations
ΔP=0 , f = N.μ, ΔE = Woth (1/2mV2 or mgh or f.x), x=V.t, h=1/2gt2
The Attempt at a Solution
Let Vi= speed of the bullet
Well, first i found the final velocity of the block on the table with the bullet inside, then applied energy law to the block BTWN the moments 1 to 2. (1. just off the table 2. on the ground & stopped.) Then i found t, to calculate D from projectile motion relations, and used all i found in the energy law; thus i found :
Vi= √(μ.L+(D2g)/4h)*√2*((M+m)/m)
Is that answer true, I could not find it anywhere else so I need verification please ...
Thanks! :)