Academic Integrity: tutoring, explanations, and feedback — we don’t complete graded work or submit on a student’s behalf.

Particle A and particle B are held together with a compressed spring between the

ID: 2199530 • Letter: P

Question

Particle A and particle B are held together with a compressed spring between them. When they are released, the spring pushes them apart, and they then fly off in opposite directions, free of the spring. The mass of A is 3.00 times the mass of B, and the energy stored in the spring was 83 J. Assume that the spring has negligible mass and that all its stored energy is transferred to the particles. Once that transfer is complete, what are the kinetic energies of each particle? J (particle A) J (particle B)

Explanation / Answer

Final momentum = = the initial momentum m1v1+m2v2= 0 4m2 v1 +m2v2= 0 since m1 = 4m2 4v1 +v2= 0 v2 = -4v1------------------1 --------------------------------------… Kinetic energy of A = E1 = 0.4m1v1^2 Kinetic energy of B = E2 = 0.4m2v2 ^2 = (16/4) 0.4m1v1^2 = 4E1.since m2 = m1/4 and v2 =-4v1 --------------------------------------… 0.4kx^2 = E1 + E2 = 6E1 92 =6E1 E1 = 15.33J E2 = 5E1 = 76.67 J ============================== Kinetic energy of particle Ais 15.33J Kinetic energy of particle Bis 5*15 = 76.67 J