Question

12. (20 points) Figure 9(A) shows an arrow of mass mA = 0.04 kg fired at a speed of VA = 60 m/s toward a wood block of mass Mw = 3.96 kg initially at rest. The wood block with the arrow embedded in it slides on a frictionless track at a speed v. At the end of the track it runs into a k = 400 N/m spring and compresses it by an amount x; [Figure 9(B)). Mw 0A = 60 m/s MA+MW k = 400 N/m MA (A) (B) X=? Figure 9 (a) Determine the speed of the wood block (v) immediately after the arrow is embedded in it. Please show all your work. In other words, NO MEMORIZED EQUATIONS PLEASE!!!

Answer 1

Mw=3.96 kg MA+MW MA = 0.0uly •VA = 60mis Using conserva non of momenkiem: Pi= Pf MAVA + Mw ww = (MATM w) 0.04 x 60 = (0.04+ 3.96) v 2.4 = и у V=0.6 mis MATMW Coro K = 400 Nm Using energy conservation: K. Einihal P. Efinal Ź (MA+Mw) v £ (0.04+ 3.96) C0.6) +x400 x xp? 2 - Ž K x ₂2 2 KA (0.6)2 100 5 Xf 0.06 m = 6cm CS Scanned with CamScanner