PHYSICS · Multi-part · A Level · Physics · Mechanics and materials · Mechanics and materials
Problem
At the highest point of its flight, a 1.0 kg firework rocket momentarily comes to rest before exploding into four fragments. Three fragments have the following masses and velocities measured immediately after the explosion:
• Fragment A: 0.30 kg moving 20 m/s due east
• Fragment B: 0.30 kg moving 15 m/s 40∘ north of west
• Fragment C: 0.20 kg moving 25 m/s due south
The fourth fragment is the remaining mass of the rocket. Air resistance and gravity are negligible during the very brief explosion interval.
(a) Calculate the east (x) and north (y) components of the momentum of each of the three listed fragments.
(b) Determine the magnitude and direction of the velocity of the fourth fragment immediately after the explosion.
(c) Explain how your results demonstrate the principle governing the motion of the rocket fragments during the explosion.