A2.7-kg cart is rolling along a frictionless, horizontal track towards a 1.1-kg cart that is held initially at rest. the carts are loaded with strong magnets that cause them to attract one another. thus, the speed of each cart increases. at a certain instant before the carts collide, the first cart's velocity is +3.7 m/s, and the second cart's velocity is -1.6 m/s. (a) what is the total momentum of the system of the two carts at this instant? (b) what was the velocity of the first cart when the second cart was still at rest?

Clara is shopping in a grocery store with her friend. each has their own shopping cart in which they want to place their items. the shopping carts are identical. clara and her friend add the same type and number of items to each of their carts. in the baking aisle, however, clara adds 20 pounds of sugar to her own cart, and her friend adds only 10 pounds of sugar to her own cart. which of the following statements best explains what clara must do to accelerate at the same rate as her friend? a. she must add more sugar to her cart. b. she must apply more force to move her cart. c. she must add 20 pounds of salt instead of 20 pounds of sugar to her cart. d. she must apply less force to move her cart.