PHYSICS · Multi-part · CBSE · Physics · Work, Energy and Power · Work, Energy and Power
Problem
Three identical steel spheres, each of mass 0.20kg, hang from light strings of equal length so that they just touch one another when at rest. Sphere A is pulled aside so that its center is raised 0.050m above its original equilibrium position and is then released from rest. It subsequently collides sequentially with sphere B and then sphere C. All motion occurs along a straight line. Assume the strings remain taut and both collisions are perfectly elastic.
(1) Part 1: (a) Calculate the speed of sphere A immediately before its first collision.
(2) Part 2: (b) Immediately after the collision between spheres A and B, determine the speed and direction of each sphere.
(3) Part 3: (c) Sphere B then collides with sphere C. Determine the speed and direction of each sphere immediately after this second collision.
(4) Part 4: (d) Compare the total kinetic energy of the three-sphere system just before the first collision with the total kinetic energy just after the second collision. State whether the kinetic energy of the system is conserved and support your answer with calculations.