Question

[20 points] Two carts are moving on a level frictionless table as shown in the overhead view diagram at right. At the instant the carts pass the dashed line on the right, their kinetic energies are the same. The mass of cart A is greater than the mass of cart B mA mB A A. [3 pts] Is the initial speed of cart B greater than, less than, or equal to the initial speed of cart A? Explain your reasoning direction of initial velocities В After each cart passes the dashed line, the same constant force is exerted on each cart. The direction of the force is to the right, and the force is exerted on each cart until it passes the solid lne on the left. After passing the solid line, the carts continue moving at the speed they had when they crossed the line. B. i. [4 pts] Is the magnitude of the acceleration of cart B while it moves between the two lines greater than, less ihan, or equal to the magnitude of the acceleration of cart A? Explain ii 5 pts] Is the final kinetic energy of cart B greater than, less than, or equal to the final kinetic energy of cart A? Explain your reasoning C. i. [4 pts] Is the average speed of cart B while it moves between the two lines greater than, less than, or equal to the magnitude of the average velocity of cart A? Explain your reasoning i. [4 pts] Is the magnitude of the change in momentum of cart B greater than, less than, or equal to the magnitude of the change in momentum of cart A? Explain your reasoning.

Answer 1

A. [3 pts] Is the initial speed of cart B greater than, less than, or equal to the înitial speed of cart A? Explain your reasoning. m mB kinetic energy = mv2 A direction of initial as mass of cart B is less than cart A velocities B velocity of cart B should be greater than cart A to keep kinetic energy КE- КЕВ same at initial point. After each cart passes the dashed line, the same constant force is exerted on each cart. The direction of the force is to the right, and the force is exerted on each cart until it passes the solid lne on the left. After passing the solid line, the carts continue moving at the speed they had when they crossed the line. B. i. [4 pts] Is the magnitude of the acceleration of cart B while it moves between the two lines greater than, less than, or equal to the magnitude of the acceleration of cart A? Explain acceleration = force/ mass a constant force is applied to both cart and mass of cart B is less than cart A, acceleration of cart B is greater than acceleration of cart A C. i.[4 pts] Is the average speed of cart B while it moves between the two lines greater than, less than, or equal to the magnitude of the average velocity of cart A? Explain your reasoning average speed = total distance traveled/time taken at t as Cart B has greater intial speed (Vi) and acceleration, its average speed is greater than cart A. i. [4 pts] Is the magnitude of the change in momentum of cart B greater than, less than, or equal to the magnitude of the change în momentum of cart A? Explain your reasoning change in momentum = Impulse force *t As constant force is applied for same time interval, cart B will have equal momentum to cart A.