PHYSICS · Multi-part · CBSE · Physics · Laws of Motion · Laws of Motion
Problem
Three low-friction carts, labeled A, B, and C, move along a straight, horizontal track. Their masses and velocities (all measured relative to the same coordinate axis that points to the right) are described below.
• Cart A has mass m and moves to the right at speed 2v.
• Cart B has mass 2m and moves to the right at speed v.
• Cart C has mass 0.5m and moves to the left at speed 3v.
The symbols m and v represent positive constants; numerical values are not given.
(a) Rank the carts according to the magnitude of their linear momentum, from greatest to least. If any carts are tied, state that explicitly.
(b) Rank the carts according to their actual linear momentum (taking direction into account), from the most positive to the most negative.
(c) Provide a clear qualitative justification for both rankings, referring explicitly to how the momentum of an object depends on its mass, speed, and direction of motion.