A cylindrical fireworks shell of mass 0.900 kg is suspended at rest from a nearly…
PHYSICS · Multi-part · CBSE · Physics · Laws of Motion · Laws of Motion
Problem
A cylindrical fireworks shell of mass 0.900 kg is suspended at rest from a nearly frictionless vertical guide wire so that the motion of any fragments is constrained to a single straight line (up or down). At the peak of a laboratory demonstration, the shell explodes into three equal-mass fragments. Fragment 1 is measured to move upward at 6.0 m/s immediately after the explosion, while fragment 2 moves downward at 4.0 m/s.
(a) Determine the magnitude and direction of the velocity of fragment 3 immediately after the explosion.
(b) Calculate the total translational kinetic energy of all three fragments immediately after the explosion.
(c) During the explosion the chemical reaction inside the shell released 250 J of energy. Calculate the percentage of that energy that appeared as translational kinetic energy of the fragments.
(d) Although the three fragments have equal mass, their speeds are not equal. Explain qualitatively how the observed unequal speeds are consistent with fundamental physical principles.